Locking on target is broken with PARS of german Tiger Heli

i had a break and just come back and i wonder is the PARS targetting broken? i ve locked a helicopter, it flew behind some trees , losing lock. after becomes visible again i cannot lock on it again, swithing to AA mislles back and forth several times does sometomes help and sometimes not. So in that time i constantly get killed or dont get the kills. it happens 3 days now. Also on ground targets, the sigh stabilistion is activated, the lok fails and my tagetting box starts wobbeling around like crazy.
This isnt fun anymore :(