My 22 incher is out of round - most likely the middle section, but possibly the lid. Has anyone found any good tricks to force the section back to round? As is, I have to bang on the lid to force it into position and I'm sure it still doesn't seal particularly well. I'd like to avoid buying a new middle section if possible. I have no idea how it happened - likely one of my kids or a landscaper didn't treat it very gently when moving it.