texts taking forever to send

My husband and I are having the same problem. It takes minutes to hours for some of our texts to send. We'll press send but the little checks that should be under the message get stuck on SMS. Yesterday it took an hour for my text to actually send at 8am. My husband finally got it a little after 9am and I noticed the 2 little checks finally showed up. Why are we paying for an unreliable service? It started a month ago randomly, but now it happens several times a day. Maybe we should go back to Tracfone.