[SalesForce] lightning:recordEditForm – ERROR: Required fields are missing: [Account__c]

I'm developing a custom lightning component which has a form to create a record (of a custom object) using lightning:recordEditForm and lightning:inputField.

One of the fields is the Account lookup field which is required.

I'm pre populating the field with the id and I can see in the UI that it's populated with the correct account but once I submit the form I get an error: Required fields are missing: [Account__c]

I also tried to remove the pre populate value and even if choose an account by myself I still get the error.

Does anyone know this problem and know what to do in that case ?

Best Answer

Checking the "Reparentable Master Detail" on the field solved the problem.