ZTC X21 FIRMWARE SPD FLASH FILE 100% TESTED

SP7731GEA_HDR_sp7731g_1h10_7.1_MRA58K_release-keys_X20

Following this problem solved by this firmware
1. Hang logo fixed 
2. LCD blanking solved 
3. Monkey virus fixed
4. Unfortunately, problem solved
5. Dead boot repair firmware
6. Storage full solved 
7. Phone Slow problem solved
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