This is for when the computer version of the Teams app is not working. Prior to following these steps, please SHUT DOWN the device and restart it. Make sure the device is connected to the internet via Wi-Fi. Try to access Microsoft Teams again. If it still does not work (likely indicated by a yellow triangle on the taskbar), then follow these steps.
Remember! Always SHUT DOWN your device when it is not in use. Updates from the district primarily get installed during the shut down/restart process and solve most computer issues!