Have you tried to restart the device? This form is handled by Google SDK.
Yes, Erel! Yesterday, I restarted all my devices on which the Google billing test app is currently installed.
But always the same effect with missing button on each device.
Currently for developing, I am using 3 devices:
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REDMI Note 10 Pro with Android 12
Blackview Tablet with Android 11
SAMSUNG S6 device with old Android version 7
On all devices the same :-(
Regards