My file not syncing and taking way too long to ope

I'm having a problem using XD- which is becoming more and more common these days. I started designing a responsive website back in June 1 and now I  am approaching the finish line, the only problem is that XD for some reason didn't sync the file since June 22 therefore I must now need to redo all work which is very exhausting considering how I am going to design for different screen sizes(3). I tolerated XD till now but this is my limit. I shouldn't have started the project with it , should have used figma instead. Plus, the customer help support is very poor. You guys don't do much than apologising and telling that "this feature is not available in XD yet". When I tried to save it as local document I cant open it saying error 86: it is not valid document or something. Is there a way I can continue from where I left off without needing to start all over? If there is no way I will never use the app and will give it bad recommendation to other people as well. When I tried to publish the document it can't do that as well.