“Musta butt-dialed ya while I was jammin’. Sorry, bro.”
:)
Or you could call repeatedly and pretend to be some old codger with Bidenheimer’s talking gibberish.
If they call back to see what’s up answer with a strong clear voice ...
“Oh, I’m sorry. That was my poor old father. I try to keep the phone away from him but every time I turn my back...”