Well, it's hard to say because we haven't identified the exact defect that you're having, but try version 13.3. https://support.quest.com/toad-for-oracle/13.3. Get the same bitness (32/64) as your current version of Toad so you can use the same Oracle client.
Different Toad versions can be installed side-by-side. So 13.3, 14.0 and beta can all be installed without problem. They each keep their own copy of settings, so you don't have to worry about any conflicts there.
Let me know if it happens in 13.3 or not.