Apple Pencil Pro not being recognised

For some reason my Pencil Pro is no longer working with iPad Air M2. I've followed every instruction to try and get it to work. iPad recognises the pencil but will not connect via bluetooth. It's 6 months old. Can anyone help with any other tips to get it to work. iOS 17.7 as IOS 18 won't load (think apple may have temporarily withdrawn it for iPad(?