There might be an issue with your cache and it seems that Android devices are mostly affected by this issue.
Please follow these steps and try relaunching the app:
On iOS
Uninstall the app and reinstall it.
On Android
- Tap on your devices’s Settings app.
- Tap on Apps (or Apps & notifications)
- Select the TSS Mobile Pro app
- Tap on Storage (or Storage & cache)
- Tap on Clear Storage and Clear Cache
- Relaunch the TSS Mobile Pro app.