I have already checked all the related questions and have not found any solution for this problem. So this is an absolutely new problem for me.
What I Have>
@Aritra, Try this
Remove quickBoot intent filter and try running it, as per the documentation we only required BootCompleted to acheive it. May be it is interrupting this.
Also one more important point to Note :
Don't rely completely or test on Mi devices as they have their own OS which halts the basic features of Android, like they stop the Push notifications services and background services just to optimize battery usage. To test this on Mi device, mark your app as "AutoStart" in Security app and then try.