Xtool.co.uk engineer replied:
Please install the newest XTOOL PS90 APK by the following free download link, then activate it and update the software.
The specific guide:
1.Go to settings and open WiFi to connect with an available router
2.Download and install the latest PS90 APK by searching the APP name or the apk link above
3.Open the PS90 application to activate with the activation code, serial number, user name, password, email…
4.Go to the “Update” menu to update the car software you desire
Note: This solution also applies to XTOOL PS90 Pro.
More XTOOL PS90/PS90 Pro problems and solutions for reference: