ID:18775 Signal "<name>" with routing constraints on line <number> of the routing constraints file (RCF) already has constraints from a previous compile or internal routing requirements and cannot be constrained in an RCF. The RCF for this signal will be ignored

CAUSE: You included a signal in a routing constraints file, but that signal cannot be further constrained. This could be because the partition for the signal has already been routed, or because the signal is routed internally to meet specific constraints.

ACTION: Remove the incorrect signal from the routing constraints file.