Iphone 5s unlocked sim is activated no service

[Laurencfox]

Recently switched from att to straight talk. Phone is completely unlocked, and my SIM card is completely activated. Carrier says TFW 18.0. I updated APN settings for my iPhone 5s, and I still have no service. I'm wondering if I need to downgrade my iPhone to an earlier version, instead of 8.1 or what? While googling carrier TFW 18.0, I get no information about it, only TFW 17.0. Help please, I havent had service for 2 days

[ST-Jean]

Hi Laurencfox! My name is Straight Talk Jean. Sorry that you’re having a problem. We need to take this issue offline so I can address it further. I will contact you directly with a private message. Please check your Forum inbox. Thank you.