Kenneth,
There are dedicated worktop joining and repair kits - Screwfix is a good place to start - but they are all intended for "professional use" - so you need to be able to mix and blend colours to get the right tone and hue, plus you'll have 99% of the stuff left over after the repair...
As an alternative idea, is the "ding" in the sort of place that a chopping or bread board, or trivet to support hot plates could be "added"? Then all you'd need to do is fill the hole with GRP resin and semi-permanently mount the bread board on top...
Lastly there are profession companies that will make an invisible repair for you...
Robert