You may have the room registered with ChanServ and Secure Ops may be set. If that’s the case ChanServ removes their @’s (room operator status) because they probably are not on the room’s access list or AOP list.
To add a user with a registered nickname to the AOP (auto op privilage) list type this command:
/chanserv aop #YourRoomName add TheirNickName
Remember to place the # before your room’s name with no space.
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