SAP Message 6A027 - Contract cannot be adjusted with adjustment type '&'

Diagnosis
You are trying to carry out a rent adjustment for a rental contract,but the adjustment type of the RA and the adjustment method selected donot match.
This case arises, for instance, if you try to adjust a residentialrental agreement using the adjustment method 'Free commercial'.

System Response
You cannot carry out the adjustment.

Procedure
This message is only to inform you why you cannot adjust the rentalagreement. No further action is necessary.