When I add events to my mac book calendar it shows up in my iPhone calendar, but when I add events to my iPhone calendar, they don't show up on my mac book calendar.
Do you have multple accounts setup on the iPhone? Is the account used on the MacBook the default account on the iPhone?
I don't have multiple accounts. What SHOULD my default account be? And how do I fix that in my settings?
If you only have one account, it, inherently will be the default.
On the iPhone, Settings >Mail, Contacts, Calendar
Scroll down. In each section there should be a 'Default Account'. So one form Mail, Contacts and Calendar. Check that the one account you have / use is set to the default.
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