Found a solution ....other may want to try with their S 10 . Brief backgound....home has NO cell service ( sits in a mountain valley) For YEARS I had an LG phone with wifi calling through Verizon and it would text ANYTHING instantly through my house wifi and land line.  Recently switched to US Cellular and a new Galaxy S 10.  After setting up everything correctly I tried texting through my wifi line land . Sometimes they went ...in a few minutes , sometimes not for an hour .  Read all these problems online that everyone seems to be having ....changed my messaging app ....even tried the Verizon Message + that worked fine on my old phone and still NOTHING . Finally started digging deeper into my wifi settings on the S 10 .   Opened "settings" icon and then clicked on "connections"  opened my home wifi connected which I was connected to under current network. There is a little "gear wheel" to the right of my named connection, pressed it to open another "settings" page for my conection .  On the bottom of this page is an "Advanced" tab. OPEN IT  !  There is a setting called "Metered network"   Mine was originally set ( probably from the factory) as "Treat as metered". Open that tab and set it to "Treat as unmetered"   , Save and exit !!   PROBLEM SOLVED !!  Texts ANYTHING now INSTANTLY !!!   LOVE this phone !  Was going to hate to have to return it because of the texting issue !  ... View more