New working fuel guage not still showing as empty tank. Looking for advice of what else to check

[Myceliumweb]

Hi. I just fixed a new fuel pump in a Citroen C3 automatic. The guage on the fuel pump works fine, but it isn't reaching the digital screen on the dash board. The car starts fine, so the fuse for the fuel pump should be fine.
I was hoping for some advice on other things I could check before paying money I don't have on someone else fixing it.
Cheers all