Doorbell mounting bracket plastic soft and unsuitable for purpose

I was given a video doorbell as a gift a few weeks ago and have just tried to fit it at the side of the door with the angled mounting bracket, holes and plugs were fine on the brick wall, but as soon as I tightened the screws for the bracket **by hand** they went straight through the plastic so isn't held on at all. I'm led to believe that the bracket used to be metal, but to be honest even some decent sized metal washers in there would help.