I recently took my Rad City 5 plus to a bike shop for a brake adjustment. I left the battery out so no electrical components would be an issue. I went to test the bike brakes and now the left brake lever is showing that it's applied when it's not. What component should I try to repair to determine if it is indeed stuck or a controller issue? The bike works as expected when the left brake lever is disconnected. I have checked the main power plug and it's tight. No fault codes or any other issues with the bike. Any recommendations that I should check before taking it to Rad for service?