Rotation changes by itself

Expected behavior

hoping to fit inside this app without any faulty rotation changes by itself, which makes us very disturbed.

Actual behavior

I want to open this app without any rotational interruption

How to reproduce

download the fanfiction reader app in the play store, open the fanfiction reader app and go anywhere, in every we want to go in there rotation is changing.

• Browser: fanfiction reader 1.57b
• Operating system: android 7.1.2
• Xiomi 4X

Recording Of The Bug