The following select should return one record, but, using FB5, it doesn't.
In FB4 it works perfectly.
I am using version 5.0.0.1306.0 of firebird server.

select aa.id, aa.id_contract, aa.numep, aa.prenume, aa.cnp, aa.marca, aa.nrctr, aa.dela_ctr, aa.panala_ctr, ab.ID_USER, ab.NUME_USER, ab.DEPARTAMENT
from sal_inperioada2('xxxx', '15.05.2024', 1) aa
left join user_cnp(aa.cnp, '15.05.2024') ab on ab.CNP_USER = aa.cnp
where ab.ID_USER = 'xxxx'