Diagnosis
You want to execute a BOM reporting function for the material andalternative you entered.
As well as the alternative, you have defined in field Appl ID inwhich usages the system should look for the alternative and in whichorder. The indicator in the field Alternative priority is alsoset.
However, the alternative you entered is not valid for the first usagewhich contains valid alternatives.

Procedure
If you want to go to a valid alternative for the usage concerned,delete the indicator for alternative priority.