I flashed my Jelly Pro with 20180308_c223v37n_dfl_pro because of longer battery runtime. After this i could not get the Jelly to turn on. I only see a black screen when i press the power button long; also with Power and Volume + or - buttons. Battery remove and reinsert in not successfully.
If i flash Android 8.1.0 back (2018092618_c223v37n_dfl_pro) all seems to be normal. How can i downgrade to Android 7?
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