ORA-21780: Maximum number of object durations exceeded
Somehow you are trying to keep too many PL/SQL objects (I mean "TYPE AS OBJECT" objects). There is an internal limitation of around 64k of these per session. This is on the client side (not on server side), so this is a programming error, not related to database administration.

Not if that matters, but if you are simply curious why this message speaks about "durations" see this doc.