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Is there a required object after the certificate object? Reasoning: If there is a required course object after the certificate, for example a follow-up evaluation, it will block the user from obtaining a certificate and completing the course. Any object after the credit claim and certificate should be optional.
Is the certificate itself required? In most cases it should be optional.
Is there a certificate object in the workflow?
Is there a certificate mapped when editing the course?
Is the user eligible for the credit type enabled, which should be mapped to a certificate?
Did the user recently change their profile, which could change their eligibility?
Are global defaults set for certificates at /admin/structure/certificates/mapping?
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