I have created a mould for a motorcycle seat, While I was releasing the former from the new mould i broke through the green gel coat where there was an air bubble.

Regarding the mould repair, someone told me you have to cover the gelcoat with a cling film or packing tape, etc... otherwise it wont fully cure. is that for all gelcoats or only certain types, and do you need to flatten the film or just lay it over?