Vauxhall Corsa fuel pump relay ?

Hello.. my car is actually Opel Corsa D with 1.2 ecotek engine but all same as Vauxhall..
So many problems, where to start....
When my battery voltage get low, it seemed like the fuel pump relay would get stuck (on when car is off) but now it does this even with strong battery..
When I try to start the car it either does nothing and flashes many warning lights including immobilizer and gives me about 12 codes(mostly from ECU and airbag) ... If i remove the fuel pump relay and attempt to start i get none of the warning lights (even without clearing codes first) and engine cranks and starts but only for a brief second as i have no fuel pump relay so no fuel pressure to continue running... In the past i have this issue twice..charged battery and replaced relay and problem seemed ok.. however this time that isn't working...
Can someone please confirm for me the proper part number for the fuel pump relay? The previous owner had something different than what I think is the correct one. The last time i had the issue i replaced with what i think is the correct relay and was problem free for 6 months (much better results than previously)

Any suggestions are welcome! I am getting so frustrated ?