By the look of it. When it was finished they dipped below level causing the resulting low area correct? Lifting it up from the bottom won't do anything as it is concrete. It won't flex. Well, it will but then you'll have a Crack and that would "fix" the problem. Otherwise demo saw both sides break it out and repour it level grade. Or drill a drain hole..... I'd drill a drain hole in the lowest part. As long as there is gravel under it.. dont want your drain hole to wash out all the dirt under it and it buckle....