@tonyjp2022 Hi, welcome to our community. If you want to MTU size, please connect your phone to the Deco network, go to Internet Connection>>IPv4 Connection>>MTU Size.

@BobetteMG Hi, welcome to our community. If your TP-Link product is a adapter, please check and share its model first on the device itself. Then we can provide further suggestions.

@Aitorlb Hi, thanks for posting question here. It is a pity that it is hard to totally understand your non-English words. I guess you want satellite Deco2(nave) connect to satellite Deco1(Recibidor)...

@Maya-2571_ Hi, welcome to our community. As my test shows, comma sign can be used in wireless password. Usually, it is recommended to set your password with a mixture of letters, numbers and symbols...

@jayfreddy Hi, welcome to our community. You may refer to the warranty and replacement policy on the TP-Link local official website.

@deaw Hi, welcome to our community. You may refer to the guide below to manage the router via Tether app remotely. How to Set up TP-Link Wireless 4G LTE Router on Tether App