Freezer not freezing

I have a Whirlpool freezer model EV201NXMQ05 that is not freezing. I have checked the fan and it is running. It does not seem to be running as fast as it has in the past (it is a lot quieter). You can hear the compressor running also. It will get down to about 20 degrees and then will warm back up to about 40 to 50 degrees. The coils are clean and it has been recently defrosted due to the drain line had froze up creating an ice block in the bottom of the freezer. It froze after defrosting. The only thing that has happened is that the door did not get closed all the way one night and was caught the next morning. It has not froze since then. It stays the same temps no matter where I set the thermostat. Any suggestions? I don’t have the money right now to buy a new freezer and had to place all my food in my daughters freezer.

Here are your parts
Parts for Whirlpool EV201NXMQ05 Freezer - AppliancePartsPros.com

First check the compressor. You can usually hear it but also should be able to feel it vibrating.

When the temperature begins to rise does the compressor stay on?

Is the compressor on all the time except when the unit goes through a defrost cycle?