Gmail Auto Denying Meetings

[DFTECH]

I'm having a little problem with an iphone and gmail. One of my colleagues uses her iphone religiously and won't use anything else. We use gmail (with our own domain) to schedule appointments. I often receive meeting requests from her and she would get an auto deny from me. I have checked my settings and there is no auto deny set on my account. And she is the only person that I auto deny to. I found other issues with iphones receiving similar problems. Has anyone else experienced this or know how to stop it from happening?