Over the last few months, I have been experiencing Roblox duplicating ‘/’ whenever I type it and not recognizing keys as I type them. I recognized this issue on both my Macs.
Other users have experienced similar problems, but it seems that their specific issues were resolved; mine hasn’t resolved.
The fix is not published. If you read what I linked, it was mentioned it’s coming in the next week.
The keys not detecting is likely an issue with your keyboard, but regardless, you should edit the “slash keys are duplicating” part out of your report to avoid having it closed as a duplicate.