When compressing pistons on fixed calipers if the rotor is deeply grooved or if the caliper cannot be forced off the rotor?

When compressing pistons on fixed calipers, if the rotor is deeply grooved or if the caliper cannot be removed from the rotor, it's essential to ensure that the pistons are compressed evenly to avoid damaging the caliper or creating uneven wear. In such cases, using a brake caliper tool or a C-clamp can help apply even pressure. Additionally, it may be necessary to clean the area around the pistons and rotor to facilitate better movement. If the situation persists, consulting a professional mechanic might be advisable.