Baseband and IMEI UNKNOWN

Hi, ive tried to downgrade MY GALAXY S4 I9500 from 5.0.1 to 4.4.2 using odin and tar file,

After the downgrade i noticed i dont have any network, i checked my settings and found out, my baseband and imei is unknown, i tried many guides to fix it but no success so far

replacing modem didnt help:/

i could really use some help, Thank you!