Sometimes when you carry on changes on your building or on its calibration sessions, (depending on your device model) clearing cache memory can be required for well running Situm app.  

In order to do it, follow the following steps:

1. In your mobile settings, search for "Installed apps" Application manager" or some name similar, it will depend on your model device.

Then, choose Situm Mapping Tool.

2. And finally "Clear Data" and "Clear Cache"

3. Open the App and login again.