How do I get rid of

I tried adding emojis into the names of some of my contacts, and since then I have been having a lot of problems. I'm not sure if the two are related or if the timing was a coincidence. Now I cant add new contacts, I can only text them by keeping their number in my inbox. My inbox and contacts constantly flashes the names, then numbers, then names, then numbers, over and over. I tried deleting the contacts with the CDATA in front but they wont delete. Also tried deleting emojis but that didn't help. 😟