attached

Hi there, can anyone help? I am trying to install a mixer tap but I’m unable to remove the connecting pipes which are attached to the copper cold and hot copper pipes. They have a hard white plastic connector attached to them. I’ve managed to disconnect them from my normal taps. Please see the...

This cartridge has a built in nut attached to it and does not seperate. Dont know the brand, and they dont sell it at the parts store. I went to Home Depot and Alright plumbing.