I had a kitchen fitted bu my builder in september. I noticed a few days ago that it has blown slightly where the join is in the laminate surface. I have no idea how or if he sealed it and if I ask he is bound to say that he did everything to regulations! What should he have sealed it with? ( it doesn't have a joint strip on )
I do think that you should go back to the person who fitted the kitchen.
It maybe that there is a fault in the worktop
or
it may have been badly installed either way get his view, he must offer some form of warranty on his work.