How to bank lock on Openwrt/EC25?

hello, im totally new to this LTE router thing. so, sorry for been a total noob.

i ordered a dual sim router on Alibaba from a Chinese seller, with two EC25-EU modules attached to it.
router has ‘Openwrt’ instead of a router softwere…

  1. when i goto 198.168.1.1 and login, i cant find a button to take me to a band locking page. i’ve seen such buttons in other router softwares. so i assume this is not a feature in Openwrt?, so do i have to use something called ‘AT commands’ to lock a band?
  2. well, i cant even find a place to type ‘AT commands’ in Opwnwrt.
  3. what should i do to lock my sim slot 1 to band 3?

thank you.

my router is ZBT-WE2806
i want to lock it to band 3 :confused: