RB 750 leases problem/keeps losing static adress

Hello everybody,
i am having a specific problem with one of mikrotiks

i am in option ip-dhcp server-leases

here i put some adreses to static as i need for my varios firewall and nat rules, all my other routers are working fine, exept this one.
on every restart/i have daily scheduler task/ i lose every thing in leases, including comments and my previosly checked static adreses?

i am hit a wall with this problem, and i can not solve it.

router had 5.25 os, i update it to 6.31, and no difference.
it keeps losing everything after every restart.
all other settings are unafected

sorry for bad english.

help please.

Netinstall is only solution.
https://www.gowifi.co.nz/userguides/perform-a-netinstall.pdf

ok, i will try that.

you are thinking that i should reinstall router os ??

Sorry for delay. I hope you managed to resolve your problem.
Only solution to this problem, as far as i know, is performing netinstall and upgrade to the latest ROS to ensure that you have the most stable platform. Had couple of routerboards with this problem.