Hi @mstevenson I'm sorry to hear this! 
What version of Retool are you running? I can check if there have been similar reports of this issue
It might be worth stepping back slightly in the history to see if a recent past version of the app works better 
Keep in mind that any changes you make on the cavas will make the past version that you're viewing the current/latest version, so just be careful when stepping back in the history.
Since you're on-prem, I'd also be curious if you recently upgraded your instance or if you see any errors in your logs