I have 3650 which its screen is blank,but after in flash return the normal,but of few days later then return blank.pls what is solution

wat firmware are u using???
did u do format user area???

I have erase,format user of area and full flash of but remain to do not change.

I have erase,format user of area and full flash of but remain to do not change.

Kindly mention which erase files u've tried?

well..now do thing..first flash it combo flash file mcu+ppm..then flash it with the latest version but differently..

I try erase with "3650_erase_flash0_flash1_flash2.fia" and "3650_erase_LFFS.fia" also i try flash with version 21.6c3,22.0c4,24.1c1,31.3c1,41.3c 1,pls help what is problem?

Try lastest version V4.17...