Query workbench DP(1.4) Drop primary index doesnt work for password protected bucket with any user

This is true for any user.

1. Make sure beer-sample has primary index and it shows up in fully-queryable buckets in workbench-UI as seen in screenshot.
2. Create a password for this bucket, so that a lock also appears in workbench UI.
3. Try dropping the primary index on the password protected bucket beer-sample without giving it a password, we see the following error:
[

{"code":5000,"msg":"GSI index #primary not found."}

,

{"original_query":"drop primary index on `beer-sample`"}

]
4. After doing create primary index on beer-sample and then trying to drop it, I get the correct message of Authorization Failed.
5. Now when I give the password and try to drop the primary index, it does show drop successful as shown in second screenshot, but the bucket is still shown under Fully Queryable buckets.
6. Also checked Indexes tab in http://172.23.105.247:8091/, the primary index did not get dropped.

Please see attached screenshots .