Please check if user belongs to security group "Calculate From Grids Group" on the scenario member.
Found below from the OneStream Reference Guide:
Can Calculate / Translate / Consolidate
When this is set to True, the user can right click on a cell and calculate, translate or consolidate data in
OnePlace, if it is set to False no calculations can be made. The Default is False.
Note: These properties coincide with the Can Calculate from Grids Scenario security group. If the
property is set to True, but the user is not in the group for that given Scenario Member, he/she cannot
calculate from a Cube Viewgrid.
Hope this helps.