Apple watch not pairing to new phone

Hi, I recently got a new phone and all of my data carried over from my old on to this one fine, except for my Apple Watch, it stopped downloading on 5ish dials. When I checked my watch again it was gone and said it’s not connected to the new phone. I’ve just gone and unpaired it from my old phone so I could then connect it to my new one but it said there was an unpaid error. Now my watch thinks it is still connected to my old phone but isn’t connected to any internet (has the red phone with a line through it) and my old phone has unpaired it. I just tried to put it on charge and hold down the power off button however it doesn’t let me tap anything (emergency sos and off button that takes me to the power off slider) except for the cancel button (as per advised on this forum) How should I go about this problem to be able to connect it to my new phone?