Sound file named '1-a' not found when using voicemail

[przeqpiciel]

I’m trying configure VoiceMail service on my Asterisk 16.9.0 and everything go fine but that one thing. Which sentence should have the file named ‘1-a’.

[przeqpiciel]

Ok, This situation is regarding to my native language.
Polish uses:
\arg \b vm-new-a ‘new’, feminine singular accusative
\arg \b vm-new-e ‘new’, feminine plural accusative
\arg \b vm-new-ych ‘new’, feminine plural genitive
\arg \b vm-old-a ‘old’, feminine singular accusative
\arg \b vm-old-e ‘old’, feminine plural accusative
\arg \b vm-old-ych ‘old’, feminine plural genitive
\arg \b digits/1-a ‘one’, not always same as ‘digits/1’
\arg \b digits/2-ie ‘two’, not always same as ‘digits/2’