Firenzi dishwasher fixing

I have inherited an integrated Firenzi dishwasher, model DW930/1 which tips forward when the drawers are pulled out because it is not fixed to the housing. I can’t see how to do this as there is no space under the countertop to get a hand in and fix a bracket. There is a lump of silicone (?) to the side of the machine and I wonder whether this was originally used to secure it but it has eventually come loose. Any advice would be extremely welcome.