Tolerances for POR

Hello.

We have SRM 5.0. ECS

We need tolerances for purchase order confirmations. The POR quantity should not be greater than PO quantity. This POR can become by EBP or SUS.

I customizing in SRM: SPRO Set Tolerance Checks  create a tolerance group  assign tolerance key (PM), Currency (USD), upper limit (blank).

The tolerance group was assign in the group of vendors in TOG attribute trx PPOMV_BBP.

However, when I make a POR in EBP and change the quantity, the system not sends any message of error and the modification is sent to PO.

Please suggest.