Yesterday there was a small window (about 90 minutes) where players could claim Raid rewards multiple times. This was during the time that we were updating our server to make the changes to Guild Bank Currency cap changes.
We have temporarily suspended the accounts that abused this issue in the time that it was possible. This suspension will be lifted as soon as we finish checking how many additional rewards were obtained by each account, and once we have removed the excess currency and items that were obtained.
Source: SWGOH Official