Doubts maintaining condition record using transaction VK11 in S4 system

Hi friends I am trying to do the pricing condition record with the transaction VK11 in S4 Hana but it is not allowing my material to enter . I checked the tables also it was maintained for both customer / material is there any changes form ECC and S4 handling this procedure . I got this error msg .

Since I am new to SAP environment kindly help

The field check has shown that the value entered for a field is not permitted.

For example, a customer number was entered, for which no entry has been maintained in the customer master.

System Response

The system issues an error message.

Procedure

Check your entries and correct them accordingly.