I was able to do back-to-back trades on Polygon without refreshing or closing the site
when this issue happens are you doing market orders, limit orders, swaps, deploying positions?
when it does happen do you get any errors? if you could open the dev console (F12 or ctrl+shift+i) and see if there are any errors there as well that would help.
are you on Windows, Mac, Linux, and what browser?
If you would be willing to share your wallet address, we would be able to look at what transactions are succeeding and failing.