I have verified device pairing to work with El Capitan.
Please try undoing the pairing on both ends (forget device).
Then open System Preferences > Bluetooth on the Mac and check that it is discoverable. Leave Bluetooth preferences open.
The launch Type2Phone and keep it frontmost.
On iPhone, go to Bluetooth preferences and initiate pairing by selecting your Mac.
If that fails, undo the pairing, fully turn off / shut down both devices and try again.
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