@serpih Hi, May I know the model number of your backup USB modem? Can I have a screenshot of the advanced>status page when fiber WAN was disconnected? If it failed to auto-failover, would a manual...

@Leoz Hi, Have you tried to put the SIM Card into the mobile phone and test call forwarding via USSD? By the way, may I know who Is your SIM card carrier and have you checked whether you have the...

@Kiran91 Hi, the official firmware has fixed the SMS issue already, and did you install the official firmware(TL-MR6400(EU)_V5_201207) before? Or you updated the beta firmware from the official...

@carbonblack Hi, The 3/4G router would be a suitable option for you. https://www.tp-link.com/en/home-networking/3g-4g-router/ But It is too early to decide which one is best for you. You could...

@Arwan @tamtp Hi, the firmware link has been updated: Manual Band Selection for 4G WiFi Routers

@wakili Hi, the previous thread is quite old, would you mind starting a new thread about your current issue? As the static IP, did you mean the APN type?