ios – Improper plurals localization kind

I’m utilizing Localisable.stringsdict in my software to localize plurals

I face the next situation. My app is localized for two languages (allow them to be EN and RU)

If the system language is one among supported (English or Russian) every little thing works as anticipated

However as soon as the system language seems to be not supported (e.g. German) and the second most well-liked is Russian localization breaks. It begins utilizing one other guidelines for plurals. I imply one, few, many and different varieties appear to be damaged

I suppose the German language guidelines are used though the app take translations from ru.lproj file (checked that)

What’s fallacious?

Each quantity apart from 1 causes the different choice for use

Does anybody have any ideas on this situation? Am I doing fallacious or one thing?

My localization appears like this:

<?xml model="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist model="1.0">
<dict>
    <key>n_courses_plural</key>
    <dict>
        <key>Variable</key>
        <dict>
            <key>NSStringFormatSpecTypeKey</key>
            <string>NSStringPluralRuleType</string>
            <key>different</key>
            <string></string>
        </dict>
        <key>NSStringLocalizedFormatKey</key>
        <string>%#@rely@</string>
        <key>rely</key>
        <dict>
            <key>NSStringFormatSpecTypeKey</key>
            <string>NSStringPluralRuleType</string>
            <key>NSStringFormatValueTypeKey</key>
            <string>u</string>
            <key>zero</key>
            <string>Нет курсов</string>
            <key>one</key>
            <string>%u курс</string>
            <key>different</key>
            <string>%u курса</string>
            <key>few</key>
            <string>%u курса</string>
            <key>many</key>
            <string>%u курсов</string>
        </dict>
    </dict>
  </dict>
</plist>