Dryer runs 20 to 30 min.then stops running.will start back after awhile.
Sounds like the motor is overheating.
You then have to wait for it to cool down so it’s internal thermal protect can reset.
Does it do it on no heat cycles?
If not then it may just be that the vent system needs to be checked and cleaned.
Or
The interior of the machine needs cleaning.
Or
There is a seal between the blower and the motor that may need replacing.
If it also does this when using a no heat cycle it may be that the drum supports and/or felts need replacing re: there is too much drag on the motor due to the drum.