OK...this being from a phone...30fps straight up? or 29.97? 30fps straight up converted might be an issue. Because 30fps is a non-broadcast frame rate. And your sequence is 23.98, right? not 24fps straight?
Try MPEG STREAMCLIP possibly...although it's not good at frame rate conversions. What I would do in your shoes is convert the footage to 29.97 ProRes...and import that. Avid does a good job of mixing frame rates properly.