FAQ

General

Q: Which Dolibarr modules are required?

The Bank and Direct debit modules must be enabled before activating the Mollie module.

Q: Which Dolibarr version is required?

Dolibarr 18.0 (LTS) at minimum. The module is tested up to version 23.

Q: Does my Dolibarr need to be in HTTPS?

Yes, it is mandatory. Mollie only notifies https URLs: without it, a payment would be collected without anything recording it in Dolibarr. The module therefore refuses to start a payment and displays a warning banner in its configuration.

Q: Does the module work with multi-entity?

Yes, the module is multi-entity compatible. Each entity can have its own API keys and its own configuration.

Configuration

Q: How do I get my Mollie API keys?

Log in to your Mollie dashboard (https://my.mollie.com), go to Developers > API keys. You will find your test key and your live key there.

Q: Can I test without risk?

Yes, leave production mode unchecked in the settings. In test mode, all transactions are simulated. Use the test API key (test_xxxx).

Q: How do I switch to production?

1. Check that your integration works in test mode
2. Fill in your live API key (live_xxxx)
3. Check the Switch to production box
4. Use the Clean test data button to delete the test accounts

Payments

Q: Are payments updated automatically?

Yes, via two mechanisms:

• Webhooks from Mollie notify Dolibarr in real time
• The daily scheduled task checks the statuses as a safety net

Q: What happens if a webhook fails?

The webhook is recorded in the log with the "Failed" status and the error message.

If the cause is temporary (busy database, setting not yet filled in), the module answers with a 500 code: Mollie redelivers the notification for 26 hours, and the payment ends up recorded. If the payment cannot match its object (different currency or amount), the module answers 200 to avoid looping and the notification remains to be reviewed.

The daily scheduled task also catches up missed payments and replays the webhooks that remained failed.

Q: Why does the module refuse to start a payment?

The most frequent cases:

• the invoice is already settled, credit notes and down payments included
• the invoice is in draft, canceled or abandoned
• the order has already been turned into an invoice
• your Dolibarr is not accessible over HTTPS

The exact reason is written in the Dolibarr logs and a message is displayed to the customer.

Q: A customer left the payment page, can they come back and pay?

Yes. If they come back while the Mollie payment session is still open, they get the same page. If it has expired or failed, a new payment is created automatically. If the payment actually succeeded, a message invites them to contact you rather than pay twice.

Q: A payment shows "being confirmed", is that normal?

Yes, for a bank transfer or an installment payment. Mollie has not confirmed the collection yet. The payment will be recorded in Dolibarr upon confirmation, without any action on your part.

Q: How do I cancel a payment?

From the payment card, click Cancel. This action is only possible for pending payments that support cancellation.

SEPA direct debits

Q: How do I set up a SEPA direct debit for a customer?

1. Create a Mollie customer (or link an existing customer to a Dolibarr third party from the Mollie tab of their record)
2. Communicate the mandate creation link to your customer (available in the Mollie tab of the third party record). The customer enters their IBAN there and the mandate is created via the Mollie API.
3. Once the mandate is active, invoices whose payment method is "Direct debit" (PRE) and whose bank account is the Mollie account will display a SEPA direct debit by Mollie button that starts the direct debit in one click.

Q: How does the SEPA button on invoices work?

The button appears on validated invoices whose payment method is "PRE" and whose bank account is the Mollie account. If the customer has an active SEPA mandate, the direct debit is started directly. Otherwise, a popup displays the link to communicate to the customer so they can create their mandate.

Q: What should I do if a mandate is invalid?

A mandate can become invalid if the customer revokes it with their bank. In this case, communicate the mandate creation link again from the Mollie tab of their third party record.

Q: Does the automatic direct debit apply to all invoices?

The MollieCheckTakePayments scheduled task processes unpaid invoices whose payment method is "direct debit", whose bank account is the Mollie account, and whose customer has a valid mandate in the module. If you want to limit direct debits to invoices linked to a contract, enable the corresponding option in the SEPA configuration.

It only works in production mode.

Q: A customer signed their mandate online but is never debited

Check that they appear in Bank > Mollie > SEPA mandates with the Valid status and the directdebit method. The selection of invoices to debit is based on this list.

Q: Who is the SEPA creditor in the mandate?

Mollie is the SEPA creditor (they use their own ICS). Mollie acts as a payment service provider on behalf of your company. The mandate will not be transferable if you change payment provider.

Accounting

Q: Where are the transactions recorded in Dolibarr?

Mollie transactions are recorded in the MOLLIE bank account created automatically when the module is activated. Payouts (transfers from Mollie to your bank) are visible in the Payouts section.

Q: How do I see the Mollie fees?

Commission fees are available in Mollie invoices (see Commission invoices). Synchronize regularly to get the latest invoices.

Per-transaction fees appear in the Fees column of the payment list, once Mollie has settled the transaction on your balance (see Payments).

Q: Does a refund automatically create the credit note?

No. The module writes the negative line on the Mollie bank account, because the money has really left, and sets an event on the invoice with the line to reconcile. The credit note remains for you to create: a partial refund has no automatic accounting translation. Same principle for a chargeback, with an offsetting entry if the dispute is won.

Q: Is an invoice in foreign currency collected in the right currency?

Yes, if the multi-currency module is active. The customer is debited the amount in the invoice currency, and the payment is recorded with the invoice's exchange rate.

Troubleshooting

Q: The "Account" page shows "information not available"

Check that your API key is correctly filled in the settings and that the mode (test/production) matches the key used.

Q: The webhooks do not work

Check that:

• Your server is reachable from the Internet
• The URL https://your-dolibarr/custom/mollie/public/hook.php responds correctly
• Check the webhooks log to identify the errors
• In test mode, use a tunnel tool (ngrok) if your server is local

Q: The synchronization fails

Check the Dolibarr logs (dolibarr_mollie.log) to identify the error. Common causes are:

• Invalid or expired API key
• API rate limits reached (too many requests)
• Network issue

Q: A message indicates a version inconsistency

Disable then re-enable the module from Home > Setup > Modules to apply the database migrations.