I have a Samsung Galaxy S9 and have been having trouble sending pictures via text to my grandkids. The picture is sometimes so slow to load into the message that I just give up. Called Verizon and they sent me an LTE extender. How do I know if it is even working? or if our phones are actually connected to it. The device webpage just says 2 connected users, but that number changes. wifi is great in the house so everything else works well but it is very frustrating that I cannot send pictures. Should I switch to ATT? Suggestions and/or comments, please.