@Britton Kroessler - If changing your OS resolution doesn’t help, you could try asking Miro Customer Support team directly by creating a ticket via this special form.
It would also be helpful for the rest of the community if you were to come back here and share what the Support team told you.
They will also want to know if you are using the Microsoft Store version or the one from miro.com/apps (there are differences - see the Desktop App help center article).
I would also suggest posting on some Surface forums too.
I uninstalled my version of the app (whatever it was), downloaded and reinstalled the desktop app and it appears to have fixed the issue. Cheers!