iMac won't hold bluetooth connection to samsung phone

I think since upgrading to ElCapitan I cannot connect Samsung Galaxy Phone (SM-G920V) with bluetooth. (It's been a couple of months since it's worked ... I just haven't had enough time to focus on fixing it). The iMac shows it as visible. I've even got it to give me a connection code and confirmed it. It shows connected for a couple of seconds and then goes to grey and shows not connected.

iMac - 27 inch - mid 2011

2.7 Ghz Intel Core i5

4 GB 1333 Mhz DDR3

Startup dish - Untitled

OS X El Capitan 10.11.3 update installed Jan 26,

1TB SATA Disk with 801.16 free

If I look at information on Bluetooth, it shows my keyboard, keypad, and mouse.

Also shows the Samsung Smartphone - Shows it is paired, configured, but has No for connected. I notice it does not show Host Connectable the way the KB, KP, and mouse do.

I did an update on phone yesterday

Any help appreciated -- I'd like to be able to transfer pictures from phone to computer.