I've been using my TP-Link M7200 router for about 1 week and it's been working perfectly. One of the key features I relied on was the ability to manually band lock to Band 3, which gave me great performance in my area.

However, after performing a factory reset yesterday, that band locking option has disappeared. Now the connection is much slower since I can't lock it to Band 3 anymore.

Can you please help me understand why this happened and how to get the band locking feature back?