Apps see my screen in Landscape even though it is in Portrait

The Screen & Display Calibration app, as well as the Helios banking app, detect my screen as in landscape mode even when it is in portrait and with auto-rotate disabled.

This explains why Helios hasn’t been working correctly on my phone for the past couple of months. The Helios team looked into debug info I sent them and found this issue.

Most apps, however, are unaffected.

This started around when I upgraded my system from 1.18 to 1.19 but I can’t be sure that that caused it.

Any idea how this happens?