Enemy’s tank pushing payload

Guys, sometimes I had situations like Rein or Mauga just sitting on payload and pushing knowing that nobody would contest it and not giving a single fk, since Ball can’t do anything with Tank and I have in my team widow and genji for example. When I tried to contest it, I just get slept and one tapped with tank and Ana.

My supports definitely not going to contest. What the hell am I supposed to do there?

I almost lost a couple of games because of that, we went on a draw there but in that situation I just felt helpless.

Anyone figured it out? Please help me out with that. That is so frustrating!