Activation error in iMessages and FaceTime after iOS 18.3 update.

Right after I updated my iPad, my iMessages and FaceTime won't allow me to activate it anymore. I have tried all of the steps from start to finish multiple times and it still says activation error. It has been one day and counting that this has been on here, I don’t know what else to do. Hopefully Apple Support will help me on Tuesday to figure out the problem or I just might have to go without it for a while since this is just my iPad and not my iPhone. Just want to know what the true problem is because I’ve only had my iPad 10th generation for 4 months. Very concerning.