How to disconnect ENOTS tube joint?

[Dor_Crank]

Hi,

This is my first time posting here. I have an Accucraft A3 model but
after connecting the two copper tubes (water tubes) from the
tender into the engine's ENOTS joints, I tried to disconnect them.
One came off OK but the other failed no matter I followed the manual direction which is:

To remove the water pipes, hold the pipe and press the ring on the fitting.

Will, it didn't work. I've searched 'ENOTS' on-line but no help.

So, I attempted to use two pairs of long nose pliers to pull the 1/8
inch OD pipe out but stopped in fear of smashing the pipe.

I did hear that people just keep both the engine n' tender hooked
up together in a long carrying box perhaps for this reason. But
I need to disconnect the pipe. It is hard to service the engine
or tender this way.

Is this an inherent problem with the ENOTS connectors? Is there
a better one?

Any suggestions?