When moving an AX database between system, especially when the primary accounts are different, you will often get an issue when running reports, reporting account x (from original system) does not have permission even though you have changed all the settings in AX to point to the correct environment and accounts.
The problem is caused because of old records contained in the table SYSSERVERSESSIONS. This table stores the AOS instances along with the user account for the AOS. When the database is moved to another system, a new entry (or entries) are created in this table, but the old ones are not removed. If the AOS account is different between environments this will cause a problem and you will need to ensure old entries are removed.