A33 overexposes when activating manual exposure for some reason even if I use the same settings as in automatics shutter

[Anonymous]

I download this app for manual video on my Sansung A33. However, when I change the exposure to manual the image gets overexposed even if I copy both ISO and Shutter Speed to the similar or even the same settings the phone was using in automatic exposure. Moving down the ISO does very little effect in the exposure compare to other phone I have (a huawei Y9 2019) I think this is an issue on other phones too. It is like the ISO gets stuck so there's lots of noise appearing on the image. Do anybody found a way to mitigate this issue?