Changing Heater Resistor (stuck half way through process!)

Hi!

Hope someone can help.

I'm changing the heater resistor (fan works only on 3+4) and have followed guides posted on this site! Great start, I've glove box out and off, and have unscrewed the heater blower unit to give a little more space.

I can see the resistor and the plug that goes into it (red green black blue wire) but cannot for the life of me shift the plug. Does anyone have any tips on removing the plug from the heater resistor. I've squeezed and squeezed those two clips and tried to tug but nothing. I've used cloths and rubber gloves to try and give me more grip!

Don't really want to have to take it to the dealer just because I can't shift a plug (bit daft isn't it!)

Hope someone has a tip!

Many Thanks