my iphone 13 will not recieve emails, it keeps saying "network error POSIX 61"

Why did my iPhone 13 stop receiving emails? I created a new email address and got a new phone # through Straight Talk, and I’ve only been able to receive 4 emails since it was created. With my new email and phone number, I’ve made a new Facebook account and tried switching my old email on my Cashapp to the new one I made, but it won’t receive the verification codes needed to complete the process. When I refresh my mailbox, it says “network error POSIX 61”