SAP Note 23948 - Customer / vendor: Screen 'dunning areas'

Symptom:

The error only occurs if a user does not have authorization to change the fields 'Dunning area' and 'Dunning procedure' via the authorization object 'Change authorization for certain fields'.
If he now tries to delete the value of all fields he can change, he cannot do this. After pressing the key, the values reappear.
Key words: FD01, FD02, XD01, XD02, FK01, FK02, XK01, XK02

Cause and prerequisites

Program error

Solution
A) Customer
SE51 - Program 'SAPMF02D' Screen '1221' - Change flow logic PROCESS AFTER INPUT.
...
LOOP.
...
MODULE XKNB5_AUFBAUEN ON CHAIN-INPUT. <-- DELETE
MODULE XKNB5_AUFBAUEN. <-- INSERT

B) Vendor
SE51 - Program 'SAPMF02K' Screen '1221' - Change flow logic PROCESS AFTER INPUT.
...
LOOP.
...
MODULE XKNB5_AUFBAUEN ON CHAIN-INPUT. <-- DELETE
MODULE XKNB5_AUFBAUEN. <-- INSERT