mikrotik licence deleting problem

0000.png
I have bought Mikrotik Ros license level 6 long term with extra channels. It has been working fine since I bought it. but since last week all the API and admin users deleted it self.
I’ve done R&D and found that when I reboot it by switching off the power all things come as usual. After running one or two hours, my license key is deleted automatically and shows the screen of license level 0 and no key. same in users as well all users are deleted and only one admin user is there and it works without password.please check the images attached here with.
Please give a solution for this issue.
001.png

For licensing issues please contact directly to MikroTik support.

Regards.