Answer
FPF, the Portuguese Football Federation, was at the center of the dispute that led to Amorim's resignation from Casa Pia. The crux of the matter was a disagreement over the release of young players from Casa Pia to participate in national team training sessions, with Amorim advocating for their participation and the FPF asserting its authority. This conflict ultimately resulted in Amorim's decision to step down as head coach.