** (Ecto.ConstraintError) constraint error when attempting to insert struct: * id_fkey (foreign_key_constraint)

The error message you are encountering, (Ecto.ConstraintError) constraint error when attempting to insert struct: id_fkey (foreign_key_constraint), indicates that there is a foreign key constraint violation when trying to insert a struct into the database. This error typically occurs when you are trying to insert a record that references a foreign key that does not exist in the referenced table.

To resolve this issue, you can take the following steps:

1. Check the foreign key constraint: Verify that the foreign key you are trying to insert is valid and exists in the referenced table.
2. Check the data being inserted: Ensure that the data you are trying to insert is correct and corresponds to the foreign key values in the referenced table.
3. Check the order of operations: If you are inserting multiple records with foreign key dependencies, make sure to insert the records in the correct order to avoid constraint violations.

By following these steps, you should be able to resolve the (Ecto.ConstraintError) constraint error when attempting to insert struct: id_fkey (foreign_key_constraint) issue.