Problem with Comments

I've have a number of posts half finished and stored as drafts, but I've been ill off and on the last few weeks and have just been able to keep up with the day job, so no time to do any serious blogging. But I have noticed a problem with my blog, which is that the comment buttons insist on reading "zero" comments, even when there are half a dozen comments. I'n not sure where the glitch in my html is -- the code all looks good to me-- but I'm afraid to tamper too much to try to fix it, because the last time I upgraded the comment function, it erased all the comments accumulated to that point. It is a quandary.