Root access blocked in Android 5.1.1,how to resolve to gain it?

My latest Datamini TWG10 (2-in-1) hybrid tablet/nettop,has Dual OS pre-installed by the manufacturer Datamini.
Windows 10 + Android-5.1.1
Both are running and functioning excellent.

In case of Android Lollipop(5.1.1),it is already rooted,but "su" shows as Root no root access , while it is checked by Root checker.

"superuser" does not function ,and it shows to manually re-root and update again.
The file directory for "su" is /system/xbin/su and permission for "su" is as : -rws--x---

How do I enable root access?
I had tried Kingo Root / KingRoot, but at the last moment it showed root failure as unaccessible.

Help required Friends.

Strangely,no takers on this thread???!!!

If the bootloader is locked you need to unlock it either by getting a code from manufacturer or in fast boot mode with simple command like nexus. If it's locked with a code and you don't have it or manufacturer is unwilling to share it there's not much you can do.

Happened with me with my honor bee which had a locked bootloader. I had to flash to a previous build version to gain root access.

topgear said:
If the bootloader is locked you need to unlock it either by getting a code from manufacturer or in fast boot mode with simple command like nexus. If it's locked with a code and you don't have it or manufacturer is unwilling to share it there's not much you can do.

Happened with me with my honor bee which had a locked bootloader. I had to flash to a previous build version to gain root access.

Thanks ,Friend for the info. and advice.
I doubt,that Datamini will ever release the code for unlocking the bootloader.
In that case do I revert back to Android-4.4.* (KitKat) through flashing appropriately?

- - - Updated - - -

The Build Number for my Datamini TWG10 Tablet is :--->
inet_phone_32-userdebug 5.1.1 LMY47V eng.inet_xch.20151009.121200 release-keys

Now is it safe and reliable to download Android-KitKat(4.4.4) having Build Number for Onda V891 Dual OS Tablet,which is :--->
inet_phone_32-userdebug 4.4.4 KTU84P eng.inet_rance.20150129.210119 dev-keys !!!???

Requesting @topgear and @whitestar_999 , and all other Friends those of whom are expert in Android.

W

i am no expert in Android

try xda forums as there might be some way but assume it to be risky.

Tried XDA forums by posting the issues,no replies till now.
Any other friends from this @TDF?

W

usually locked rom/lesser known/small manufacturers have little dev support & one of the reason why ppl suggest to go for brands like motorola if dev support is needed.unless root access is absolutely needed i suggest sticking to 5.1.1.

whitestar_999 said:
usually locked rom/lesser known/small manufacturers have little dev support & one of the reason why ppl suggest to go for brands like motorola if dev support is needed.unless root access is absolutely needed i suggest sticking to 5.1.1.

I understand your advice and suggestions,Friend. The peculiar part is that the Android version-5.1.1 came with root installed,but it has been kept in "non-access/unaccesible" mode. Simply put you can't run the "su". YOU DON'T HAVE THE PERMISSION.
Even If I could get access or enable the permission that would have been great.