I would strongly suggest dropping your temperature to 180 when retracting the filament out of the machine, this should prevent the filament getting too gooey and sticking to the PTFE tube. If you need to replace the tube you should be able to replace it with some Capricorn tuning that is readily available online and usually also available from the creality store. It will just be a case of cutting a piece the same size as the one in the hotend and swapping them out.