See this topic Proofpoint and Digital Ocean = Real Problems - #7 by vele
It seems that the DO Netherlands and UK are not listed on Level2 (at least some of them), check here UCEPROTECT®-Network - Spam Database Query
It seems they will never be delisted from Level3 but Level3 is not a problem. Just find a clean address (Not in red).
Migrate to those regions. When you are assigned new addresses check them first on https://multirbl.valli.org/
If they are listed release and renew.