I just received my second H9 yesterday and had the same exact problem with both my iPad Air and iPhone 6. Note that in experimenting, I was able to connect to both if on the "bluetooth" screen of the Settings App if I click on one of the h9's to connect, and then quickly try to tap the other to connect before the popup asking me to allow the h9 control app to access my h9. I was able to accomplish this a few times last night on demand, so I was happy to be able to control both my h9s. Let me know if I can gather any info to help debug this.
