Thanks! It works.
The bug is remaining after this fix! I changed all files this method and checked its and I got : Error — Perl execution failed Modification of non-creatable array value attempted, subscript -1 at /usr/share/webmin/bind8/edit_recs.cgi line 94. OS: Debian 4.19.208-1 (2021-09-29) x86_64 Webmin set Russian language