Hello Jan,
as a workaround, you can manually delete data volumes with the 'dbmcli ... db_deletevolume' command. Just specify the name/id, preferrably the volume you have added last and it should be deleted and any pages distributed to the remaining volumes.
But of course the "data area shrinkage" feature is supposed to be working, at least I am not aware of any current problems.
Maybe the database could not completely remove all pages from one volume...
If you want me to take a closer look, please upload the 'KnlMsg' and 'KnlMsgArchive' files (and please reformat the text via 'protconv' first):
1. goto MaxDB rundirectory:
'protconv KnlMsgArchive > knldiag.err'
'protconv KnlMsg > knldiag'
2. You can use this SAP Mobile Documents link for upload:
https://mdocs.sap.com/mcm/public/v1/open?shr=FagWTUgbHnsu76vWE5N8uXjt1AWns3S_nF2EvvCrGqk
Regards,
Thorste
Edit:
I have corrected the upload link - it should now work...