MaxL ASO clear data statement does not clear data

Summary

MaxL ASO clear data statement does not clear data

Content

We are on version 11.1.2.4, Win Server 2012 Standard 64-bit. The following ASO MaxL statement:
    alter database ''.'' clear data in region "{...}" physical;

does not work if {...} contains anything more than 1 tuple. The statement executes succesfully (and unusually fast) but the data does not get cleared from the cube!

Did anyone have such issue and what can be advised?

Thanks!