Help with Index/Match on two criteria

Hello folks,

I have a field that I need to populate from a datasheet containing computer or phone tags.

The formula I've tried to build looks up staff initials, then goes to find either if the device is phone or computer.

I'm getting odd results and have tried a few things but no joy.

Funny thing is one of the formulas works, the other not, yet only one parameter changes.

Sheet attached - the data will always be text string in this instance.

Any pointers are welcomed, thanks,

Ian