tr newlines no output

root@clone-messagerie[10.10.10.19] ~ # mail.user.detail "$mail"
*************************** 1. row ***************************
FN:BOUKHAROUBA  Sedik
[email protected]
TITLE:Sous-Directeur de station
X-DEPARTMENT:Radio M’Sila
TEL;TYPE=home:5028
BDAY;VALUE=date:2023-10-24
root@clone-messagerie[10.10.10.19] ~ # mail.user.detail "$mail" | grep -E 'TITLE|X-DEPARTMENT'
TITLE:Sous-Directeur de station
X-DEPARTMENT:Radio M’Sila
root@clone-messagerie[10.10.10.19] ~ # mail.user.detail "$mail" | command grep -E 'TITLE|X-DEPARTMENT'
TITLE:Sous-Directeur de station
X-DEPARTMENT:Radio M’Sila
root@clone-messagerie[10.10.10.19] ~ # mail.user.detail "$mail" | command grep -E 'TITLE|X-DEPARTMENT' | tr -d '\n'
root@clone-messagerie[10.10.10.19] ~ # mail.user.detail "$mail" | command grep -E 'TITLE|X-DEPARTMENT' | tr -d '\n' && echo
X-DEPARTMENT:Radio M’Silatation
root@clone-messagerie[10.10.10.19] ~ #