Nozzle of printer slipping and filament lifting  

Nozzle of printer slipping and filament lifting

Every time my prusa i3 reaches about 40-60 mins in it just stops extruding and the motor starts slipping on the filament resulting in having to
restart the print only to get the same problem 40 mins in again.

Also when I preheat the printer to pla it used to go to 220/220 on the nozzle but now it only gets about 205 to 210. The bed is fine at 50/50
To try to keep it hotter I manually a just the temp to 235 and it stays at around 215 to 220.

The second problem is that if I try to print things vertically the support material is very rough ending in the extruder ripping it away from the bed.
This also can happen for some normal prints as well when the printer leaves a small blob of filament and the nozzle just ripping it off.
The bed of the printer is level as I can print something fine that would only take 10 mins and I have also sanded down the bed to get it level as well.

Please do you have any idea what one of the problems might be because if I want to print anything I have to watch it the whole time or it messes up, and even at that watching it just shows me that I wasted an hour looking at something I would have to restart anyway.