Triplet markings in multiple voices

Hi all,

I am writing a Preces and Responses and in one of the responses, I have a triplet rhythm and bass divisi (two voices). Because there are two voices, there are two triplet markings, but I only want one triplet marking for both voices (it is obvious from the score that all parts sing a triplet rhythm). However, when I try to remove the triplet marking for the second voice, it reverts to two notes.

Is there any way of hiding one of the triplet markings so that there is only one triplet marking for both voices, while retaining the triplet rhythm?

Use Properties Number and Bracket:
Zrzut ekranu 2019-08-16 o 12.47.01.png
Zrzut ekranu 2019-08-16 o 12.47.03.png

Thank you very much Nikola!