Adblue hose connector

[jubbly1999]

Hello everyone,

I wonder if someone can please help: I'm trying to disconnect the adblue tank filler hose from the filler neck hose and I'm not sure how to operate the release mechanism on the connector. I've attached a pic of the connector in question. I've sprayed hot water on the connector (several times) and cleaned a lot of the dirt off. The connector itself moves slightly back and forth plus I can twist it slightly both ways so I don't think the connector is seized. The green tab pushes in easily and it moves freely but I can't access the opposite tab as it's right next to the smaller pipe. The hole in the tab makes me think I need to pull it out but it doesn't pull out at all. I've sprayed wd40 into the hole in the tab and around the end of the connector. I think to disconnect I need to push the pipe in, operate the release mechanism and then pull the connector off, but what is the release mechanism?

This is on a 2017 transit 350, L3H3, rwd, 2.0l diesel 130ps, YMR6 engine.

Any help very much appreciated.