I can't see the last 2 on the model number the serial number is wa54900586. The refrigerator won't get cold tried turning up to 7 on the control knob but nothing. Also the seal on the bottom of the door is hanging down. The refrigerator is running normal but it is really warm.
You will want to pull the rear cover in the refrigerator compartment and check the frost pattern of the coils. If there is a little frost pattern, meaning the just a little on the coils where they come into the unit or through the first loop then the issue would be a sealed system issue. If the coils are impacted with ice then it would be a defrost issue. If the coils have a nice even pattern top to bottom then check to make sure that the fan is running.