[email protected] fails to load but not [email protected] - are both needed in linux boot?

by running systemctl status postgresql* i found that the values for lc variables were wrongly set. I changed them to en_US.UTF-8

lc_monetary = 'ar.UTF-8'            # locale for monetary formatting
lc_numeric = 'ar.UTF-8'         # locale for number formatting
lc_time = 'ar.UTF-8'                # locale for time formatting

in file /etc/postgresql/13/main/postgresql.conf

then I run systemctl restart postgresql* and systemctl restart postgresql*