It looks like when you press the tab button multiple times it works. This is in line with a problem I am encountering with the input field where if you one input is focused and you want to focus another input you have to click that input twice. I think the best thing you can do is submit a bug report and hopefully the bubble team can find a solution for this problem.
All of the fields (and the text above them) are part of the same group. Which I would imagine would be the best way to do it. If I split them out into separate groups, I feel like that wouldn’t work either.