The first character joined by the @& ligature tie disappears when I type them in Excel. Using e@&i as an example, the e displays like normal. When I hit the @, the voiceless diacritic appears above the e, as I supposed it should. But, when I hit the &, the e disappears along with its diacritic, and the right hand side of the tie appears under where the second character will appear. When I hit the i, an i appears above the right hand side of the tie. And, when I hit Enter and leave the cell, the entire tie appears, with the i above the right side, but nothing where the e should be.
The sequence forms correctly in Notepad, and I can copy and paste it from there into Excel. Also, the #& tie above the characters works fine in Excel.
(This is not an important matter (for me) that needs your time. I have two means of getting a tie, Notepad, or use the upper one. But, it would be nice to have it fixed eventually.)
Windows 10 Pro
Excel 2016, (Office Home and Business)
Keyman Desktop 10.0.1093.0
SIL IPA Unicode 1.1.1