iPhone 6 Calendar will not allow any entries to be made.

Hello Boffney,

Welcome to the Apple Support Communities!

I understand that you are trying to add a calendar event on your iPhone, but it doesn’t appear to be working as you would expect. The linked iPhone User Guide below, starting on page 83, explains how to use the Calendar app on your iPhone. If this is the same process you are going through and the issue continues, please let us know.

https://manuals.info.apple.com/MANUALS/1000/MA1565/en_US/iphone_user_guide.pdf

Have a great day