Propane RV quick disconnect not locking

Just to make it clear: any information about only 1 or 2 propane quick connect ports being out there is misleading. There are numerous proprietary propane quick disconnects, created to lock people into buying proprietary hoses. Some RV manufacrurers used them earlier to lock peope into that racket. These are useless now as no connectors for them are avilable any more. 

 Proprietary propane quick connects look identical to sandard ones but are not compatible. (what a racket, there should be single standard mandated by Federal law). They do not even make parts to connect to those older proprietary ports anymore, impossible to find,in this case obsolete Cast Products part (no, nothing falsely advertised online to work with it will).

$12 amazon standard female LP quick disconnect replacing this obsolete one is a fix, 15 min effort, anyone can do easily!

According to my local RV dealer, there are two such disconnects commonly used on RVs and installed by the RV manufacturer. You cannot distinguish them visually easily, but they are completely incompatible. He sold me one of each of the male ends (with promise he'd take back the one that wouldn't connect) for about $7 each. I don't pretend to know everything about such connectors, but one thing is certain: there are at least two intended for propane, and they are NOT compatible with any of the ones intended for compressed air, which is a whole other can of worms. 

It appears you have the wrong male end, and need the other one, whichever that is. Rather than going to a propane supplier, I'd go to an RV dealer for help.

Looking like proprietary quick disconnect after I pulled the part number, hoses for which are no longer sold and is known to cause problems. Some RV manufacturers installed thar proprietary stuff to lock people into the racket. Im going to see if propane suppliers can locate it on Monday but looking like entire quick connect would need to be replaced. Since I only need this to empty propane tank probaby wont even bother may be just use the oven

I talked to online propane stuff supplier. Propane quick connects aren't the same, trying random hoses is a waste of time. There are proprietary propane quick connects out there which will only fit matching stuff. There are also low and high pressure quick connects which may both be 1/4 but wont fit. May be the hose I got has high pressure fitting on it even though its supposedly low pressure hose. Who knows its hard to tell but it measures like low pressure end shoud. I emailed them pictures may be they will figure it out.