[exim] exception for not setting a header does not work

Good evening,

i try to add an exception for not setting a header if the sender is the one
listed in /etc/exim4/no-spf-senders. The code is listed under "
acl_check_rcpt: ".

So this works in general (setting the header):

https://pastebin.com/0kFmv2fy

Why does adding this line not work as expected?

!senders = lsearch*@;/etc/exim4/no-spf-sender

I want the sender foobar@??? not to trigger the "add_header", but
it still triggerst he "add_header"

Sorry, can't use pastebin this time, because they say this code is
offensive...

warn message = [SPF] $sender_host_address is not allowed to send mail from
${if def:sender_address_domain {$sender_address_domain}{$sender_helo_name}}.
\
Please see http://www.openspf.org/Why?scope=${if def:sender_address_domain
{mfrom}{helo}};identity=${if def:sender_address_domain
{$sender_address}{$sender_helo_name}};ip=$sender_host_address

log_message = SPF check failed.
!senders = lsearch*@;/etc/exim4/no-spf-senders
domains = example.cpom
condition = ${run{/usr/bin/spfquery.mail-spf-perl --ip \
             ${quote:$sender_host_address} --mail-from \"$sender_address\"
--helo \"$sender_helo_name\"\
             --identity \
             --scope mfrom  --identity ${quote:$sender_address}}\
             {no}{${if eq {$runrc}{1}{yes}{no}}}}
add_header = spf_failed

root@mx: cat /etc/exim4/no-spf-senders
foobar@???







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