KW T680 Compressor problem

Ok I had a compressor discharge line replaced a few weeks ago.
Today I just started driving, I saw transmission low pressure low alarms. I pulled over to the shoulder and I noticed air coming out of a hole below the oil filter at the compressor.
I've been idling for a little while and I am not building up air pressure above 100 psi; it is holding at 80 psi.
What do you think that the problem is? Thank you.

 

Now this is weird. I observed my pressure build up to normal 125 psi after a while, air was no longer leaking at the bottom of the compressor oil filter.
I released and set both of my brakes a few times and observed the pressure build back up.
I got curious I released and set my brakes a few times again but I drove slowly back and forth on the shoulder of the road to observe the compressor build the pressure back up and it did so quicker.
Everything appears normal now??

 

Yes I confirmed that it is the air dryer. I read oil on the label somewhere earlier.

 

The problem was the purge valve. The first ship I went to tested it out and didn't see a problem with the valve. Then the same issue happened the next day when I was driving; got the purge valve replaced now everything is ok