Lost all messages due to sending failure.

For the past few days I have had trouble sending imessages to my friends. When sending the text, I'd often get the "send as text message" option. When I choose to "send as text message" there will be a blue loading line and message saying "1 of ...."(however many text I had sent). If the person I was texting received my text and replied I wont get a notification I have to stay in the message to see before they disappear. I tried disababling the app over and over again and nothing worked. After realizing my text were being arranged out of order, disappearing, and still struggling to get them to send; I restarted it. After restarting my phone, I lost EVERY SINGLE THREAD in my messages. This has happened about 3 times this week. I keep losing my messages and I cannot restore them. When I last looked in my storage it said I had 2GB of messages but there are 0 messages in my messaging app. Please help I have a lot of messages I'd like back and important information I need to retrieve.