Gas Hob Seal

[nuttynic999]

Hi 1st time here, can anyone help? We employed a company to install worktops, gas hob and sink. I sourced the hob myself, which I gave to fitters along an installation manual and fittings including an adhesive sealing strip. 2 months after I have found they did not just the strip to seal between the worktop and the hob base. The hob base is made of mirrored glass.
You can probably guess the effect what stray crumbs and moisture has had. I have emailed and written to company no reply as of yet. Any advice.