DFS0557I STOP REGION NOT VALID-REGION nn IS BMP.
Explanation
A /STOP REGION command has been entered for a dependent region in which a BMP is processing.
System action
The entered command is ignored. The IMS and the dependent region, which is identified by nn, continue running.
Programmer response
Determine if the correct region ID was used, or use the ABDUMP form of the /STOP REGION command.