I checked but couldn't replicate the issue you are describing. You should have no issues submitting proposals. Could you please try clearing your cache and cookies or using a different browser? If the issue persists, please send us the screenshot of the error from your end so that we can check and assist you further.
I'm having a similar issue, I can't submit a proposal because it keeps telling me to update my address - which I've already done. I've cleared my cache and logged in and out, same issue.
Appreciate any assistance, thanks.