A lot of tits are looking quite tatty at the moment, due to wear & tear of breeding season. Coal tit would be most similar in colour to crested, whilst blue can appear to have a crest, but wrong colours:
https://kensingtongardensandhydeparkbirds.blogspot.com/2019/03/a-blue-tit-emerged-from-nest-hole-in.html?m=1

I know it seems unlikely but I am convinced I have had a crested tit on my bird feeder in Chard in the last few days. Being a very bad ‘birder’ I assumed it was a ruffled blue tit until I checked with various pictures. Unfortunately I have not managed to get a photograph so far. Interestingly, it was here last year as well. Time may clarify things….