[Dovecot] sieve problem email silently discard

hello folks hello Timo hello all the guru

I met a few times the problem or an email that passes through a sieve script is silently discard after delivery but never returned to the inbox

all testimonials are welcome

 http://pgp.mit.edu:11371/pks/lookup?op=get&search=0x092164A7 gpg --keyserver pgp.mit.edu --recv-key 092164A7