for( split(/[\r\n]+/, $content) ) {
    if(($_ =~ m/35=8/)&&($_ =~ m/$tag1/)&&($_ =~ m/$tag2/)){
     printf $_;
    }elsif(($_ =~ m/35=9/)&&($_ =~ m/$tag1/)) {
     printf $_;
    }
 }

##</code><code>##

Message dump:
8=1034=DFG55=TEST90=23435=D
19 06/02/23 11:18:33:984 Sent Message

##</code><code>##

8=1034=DFG55=TEST90=23435=D

##</code><code>##

19 06/02/23 11:18:33:984 Sent Message