I can't drop items with luckperms, nor can anyone else in groups. Is there a command to fix this?

luckperms just deploys the permissions. Are you running Sponge, nucleus, grief prevention or something other that will affect this? Please give more info as well as version numbers.

We are using Nucleus 1.5.2, and the latest versions of Grief Prevention and Spongeforge

then you will need to test. GP has an item protect module in config. if you disable this are you able to drop items? if so then its a GP permission that is blocking it

Not directly caused by LuckPerms.

You can use the verbose command to attempt to diagnose the cause of the issue.
https://github.com/lucko/LuckPerms/wiki/Verbose