Need To Escape Platinum HELP

Hey everyone.
I had very bad placement matches ended up loosing almost all of them. Normally I’m a at Diamond, but I have been placed in Platinum.

My matches have been terrible and I cannot escape the rank, my friends won’t even play competitive with me to lend a hand. :frowning:

I play Support and Tank, from the UK.
Mostly Lucio, Orisa, Moira and Winston.