Admin: Unable to create an instructor account if the same email was used for a student account

[damithc]

v9.0.0.beta6

I received an account request from someone who used TEAMMATES as a student before, and joined TEAMMATES using her Google account before.

Problem: The following error appears and I approve her account request.

However, the user doesn't currently have an instructor account, and cannot login as an instructor.

PS:

I can still add the instructor using the previous form (i.e., manual entry) but not the new account request processing workflow. That is, (a) works but (b) gives the error mentioned above.