Sync between Mac and iPhone causing Duplicate Entries

Hoping someone can help a Newbie. Loving Omnifocus. I’ve noticed that my iphone app does not sync well and I often have to manually hit sync for it to work.

This AM, I spent an hour cleaning out my inbox and creating projects. I then went to my iphone about 2 hours later and noticed my inbox was still full. I hit “sync” and nothing happened. I then come back to my mac and now my inbox is full again with everything I already cleared out this AM.

Is this an error on my part? THANKS!