You may see the following assertion failed error in your DSA log when resetting (or setting it for ther first time) a password value:
[6] 20230214.150422.373 Assertion failed [Password exceeds maximum size allowed] (/net/cadir-master/release/B14_1_02.new/dxgrid/src/dsa/dxgrid/caCompare.c175)
Release : 14.1
The above is not related to Symantec Directory. There is no such limitation on number of characters that a password value can have. This limit can be imposed at the application level.
e.g. If you are using Directory with IDM (as Identity Manager User Store) or SSO (as SiteMinder User Store or Policy Store) etc, you may have password policy rules set at those application level. Check with those applications to see if there is any restriction/rule in place that limits the number of characters (size) that can be allowed in a password value and adjust accordingly.