Ties between staves

I’m trying to follow the instructions as to how to tie a note to another in a different stave, which is essentially to select two notes of the same pitch and hit T. But it doesn’t work with the two Fs here (end of beat 1 RH to beat 2 LH). Where am I going wrong?
image

It could be that there’s an F# in the key signature, or that you’re not in Write mode, or that you’re selecting something in addition to the two Fs (you should click the first one and then Cmd/Ctrl click the second, in order to avoid selecting anything else).

The picture itself doesn’t suggest anything untoward.

I’m very sorry - I read the instructions too literally, forgetting that ‘T’ is itself a keyboard shortcut which I’d changed to something else months ago. Apologies.