Derek Rankin

I folks the phone gets to about 33% and recently seems to go a bit crazy. When flying at destination, its o % charge. Have done the reboot using both side buttons and starts ok again. and seems to charge fine o fast charge But charge isnt lasting long.. and then as i say drops to nothing. when put on charger at times shows 33.. sometimes nothing only just stated doing this about 2 weeks ago. out of warranty. mint condition. well looked after thoughts?????