A user's OTP credentials are generated using different OTP profiles with different USAGE TYPEs.
Restapi is able to fetch only the default credential associated with the profile of the organization when fetching the credentials. User credentials other than the default ones cannot be retrieved as of now.
Release : 9.1 SP3
Symantec-StrongAuth-DE558128_DE558130-HotFix is released to resolve the issue.