Broken p-trap?

In attempting to clean p trap under two kitchen sinks, the trap came apart at what looked to me like a corroded 2” slip nut. There was no washer however and I am wondering how a slip nut could go ever go what looks like a permanent washer of some sort that is a part of the PVC itself. (See blue arrow). How is that elbow connection supposed to work?

Thats a pvc street 90. You cant use slipnuts on that. It has to be glued. Whoever did it the first time didnt know ehat they were doing

Thanks so much! Any thoughts as to what I need to do now, and why sink may have clogged in the first place? The trap was not clogged. See added pictures.

If that's a kitchen sink then it most likely was a grease clog years and years of food particles and little bit of grease from washing the dishes builds up in the pipes and eventually clogs

That looks like an island sink set up. That loop goes back down and ties into a vent. They do it that way because there is no wall to take up a vent in. Try running a snake through while you have the trap apart.

It's not a slip joint. The nut for union popped off of the 90.
The nut is not supposed to come off.
best to just replace it.

Yours is like the right trap, nut on the 90.

House is 17 years old and we just bought it 6 months ago. Actually it is on an exterior wall, but there is also an island as well. The female end of the trap that the street elbow was in has a recessed what I would call receptacle in it. See pictures showing how it all goes together.

I ran an old fashioned manual snake about 20 feet down through that clean out plug and felt nothing. How would you approach this, i.e. what fittings would you suggest to be used, etc.

Mr-David: you nailed it. That must be what happened. The nut is medal and all corroded which I guess allowed it to come apart when I unsuccessfully tried to loosen it. I took it to stores and they all told me I needed a 2 inch slip nut which lead to my original post. A 2 inch metal one is on the way from Amazon. Can it be Popped on?

My mistake for the wrong information about the fitting always great to have a second or more opinions

Not sure if that will be the right nut but if it's in the mail worth a shot.
I have never seen a plastic p-trap with a metal nut until now.

This maybe the same one. made by Charlotte

https://www.ferguson.com/product/1-12-in-pvc-dwv-p-trap-with-chrome-plated-nut-pdwvptcnj/_/R-45386?skuId=45386

you could just maybe glue the thing back together.

If I had to rebuild that whole mess I would replace the santee and bring it up 4 " to clear the stop valves and turn it toward the sinks.

P-traps drain better when the water flow is going vertically into it rather than a 90 in an a 90 out.

Yep, it is the one by Charlotte, and believe it or not my son was able to get the nut back on and the whole thing back together. Bad news, though is that the snaking we did did not help as the clog must still be there. It must be way down as I got a surprise when I opened the clean out and water gushed out. Not a plumber!

Have heard that “hair and grease” from Home Depot is good, or do you think I need plumber/rotor rooter?

You have to snake it to mainline might be 15 feet might be 30 you will know when you are in main snake will get easier to push unless you are going up the vent. One way to tell is if snake is easy to pull back you in vent if it is hard you are going the right way