Fuji cherry not flowering yet

Help please! I think I’ve killed my Fuji cherry (or at least caused some serious pathology probably through neglecting it). It still hasn’t blossomed and I’m thinking if it hasn’t done so yet it probably won’t. Could the late frosts have done it? Or was there something I was supposed to do to it that I didn’t? It has small buds and has done for a while (months) but they haven’t done much. It’s in a container in a sunny south facing spot and was very happy last year. We are in North Yorkshire if that makes any difference. Help!