Not sending Text Messages With Moderate Connection

My brand new phone does not send text messages when it has only a moderate connection. This most notably applies at my home. I can still receive messages just fine, but I am stuck with any reply as "Sending". I have to get to a location with better reception and then send a new text, and everything will then go through.

Wifi does not help. If anything, it makes it significantly worse. On occasion, disabling wifi and sending messages again works.