That is a high temperature for fermenting lagers. That aside, many extract brewers encounter the 1.020 dilemma. It seems to be somewhat common, from what I've read about on here. In my mind, you have a couple of options. You can add more yeast and hope for the best, you can add amylase (just a tiny amount) to help the yeast out, or you can blend your beer. It just depends on your resources. You could add the bread yeast if you want and it won't add too much off-flavor since most of the fermentation is already over...but there's no guarantee it will even work. If you kept the beer in primary this whole time, then you probably have plenty of yeast. That being said, I have no idea about your processes and you should be more specific about how much yeast you pitched and how strong your brew is.