Reminder app on Macbook shows only a blank window
I recently sent my Macbook in for service and was sent back wiped with Sierra installed. After re-installing everything and updating to Catalina again I cannot for the life of me figure out how to get the Reminders app to show anything. They show on iPhone, and have also tried turning off Reminders and Calendar in iCloud menu on desktop and restarting a few times. Any answers for how to solve this? Thanks.
MacBook Pro 15", macOS 10.15