Hi @GokulaKr ,
While upgrading from SP 17 to SP 21, did you have any custom permission ACLs which got overwritten by SP 21 installation?
Please check rep:policy of your folder in CRX if you had any custom policies and try to add it back if it got overwritten.
Also, creating and editing launches requires access rights to /content/launches
- as with the default group content-authors
.
Check if you have access to it or not?
-Tarun