Help...remove Google from Pixel Buds Pro 2

Long story short, need to return my PBP2 to Amazon but can't find a way to unlink them from Google account before packing them. How can I do it? I have already done the "Forget Device" but can't factory reset them properly even after following a couple of YouTube tutorials. Any help will be greatly appreciated.

Long story short, need to return my PBP2 to Amazon but can't find a way to unlink them from Google account before packing them. How can I do it? I have already done the "Forget Device" but can't factory reset them properly even after following a couple of YouTube tutorials. Any help will be greatly appreciated.