Completing specialization which I am already enrolled

Hello! I am enrolled in the “Organizational Leadership” specialization introduced by Northwestern University. The Specialization consists of 5 courses and 1 capstone. My enrollment is sponsored by the State Employment Agency.

Up to now, 4 courses are already completed and a certificate was issued.

The PROBLEM is, when I tried to go to the 5th course (part of the specialization, for which I already enrolled) it stated that I am already enrolled and the relevant button is not active. So I cannot move further.

Need your advice on how to proceed in order to finish the specialization for which I already committed a lot?

Thanks! @metafans