How do I fix 'Network error (POSIX 50)' and Wi-Fi issues on iPhone after Airplane Mode?

I usually put my phone on airplane mode before going to bed. I woke up this morning and removed my phone from airplane mode. The wifi ought to come on automatically. It did not. I put off the wifi and put it on, it only blinked. I forgot the network and reinstalled the wifi. No luck. My emails would not refresh. I get the code Network error (POSIX 50) for 2 and Network error (POSIX 60) for 1. I have tried restarting the phone, no luck. I have gone through the mail settings, i am not sure what I should be looking for. My VPN is off and wont turn on. Everything is slow without the wifi.

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Original Title: How can I fix Network erro (Posix 50). Also my wifi is not working on my phone