Can't make phone calls with new Samsung Galaxy S21
I changed phones from pixel 2 to Galaxy S21 a couple days ago. Everything, including messaging, browsing on wifi and data, and receiving calls all work flawlessly. However, I cannot place outgoing calls. No matter what number I try, an automated operator says "your call cannot be completed as dialed." I have two phone apps for some reason; both do not work. I can't access the "supplementary services" setting in the "call settings" menu because it says "Failed to read data" and
"something went wrong. Check your SIM card or network connection, then try again."
Since everything works except making calls, I'm pretty sure the SIM card and the network connection are just fine.