Gold bars that I have earned are erased when I return to DuoLingo. I am getting discouraged.
Don't be discouraged. They are an incentive to keep practicing skills you have learned so you won't lose them. I spend the majority of my time in german just keeping my bars up.
Keeping them gold in never a requirement.
If you are feeling discouraged, just ignore the gold-ness of your bars and move on. You know what you know and don't need bars to tell you otherwise.