Thanks for trying those steps.
Since you are still having this issue, we would like you to reinstall iOS.
First, use this article to make sure that you have a backup of your iPhone: How to back up your iPhone, iPad, and iPod touch. Then, use this article to reinstall iOS: If you can‘t update or restore your iPhone, iPad, or iPod touch. Note: This article is intended to be for a different issue but following steps 1-5 will help you reinstall iOS without erasing data.
Let me know if you have any questions.
Cheers.