Horror of all horrors! I made my usual batch of Seville Marmalade last year  and went to use the first jar this morning - having made a bumper lot in 2015.. Every single jar had mould growing around and under the waxed discs. OK - I may have made an error - although I'd never admit to it :-)) Can I scrape off the mould in each jar? Would I have to reheat and re pot the marmalade? It's all so distressing.