I have a Samsumg Galaxy Note 9 phone and an iPad Air (3rd Gen). I use both with Snapbridge. I also have 2 cameras: D5600 and Z6II.
I have to go into the setup menu,
get to the Bluetooth option (under "Connect to smart device" on the Z6II, stand-alone on the D5600)
select the correct device.
Then it allows me to use that device to download my photos.
Hope this helps - a little!
(Sorry, looks like the pics are in reverse order. They show you n the correct order in the list..)