Cannot delete row (selection condition from foreign key dependency)

What causes this issue?

You cannot change or delete the selection condition, because it comes
from a constant in the foreign key relationship.
When two basic tables are linked by a foreign key containing constants,
this acts like a selection condition on the field in the check table.
To make this clear, the selection condition is displayed in the view
definition.

System Response

You cannot delete the selection condition containing these constants.

How to fix this error?

Error message extract from SAP system. Copyright SAP SE.