geting error/warning for plurals : "The quantity 'one' matches more than one specific number..."

Background

I work on an app that has many translations inside it.

I have the next English plural strings:

<plurals name="something">
    <item quantity="one">added photo</item>
    <item quantity="other">added %d photos</item>
</plurals>

and the French translation:

<plurals name="something">
    <item quantity="one">a ajouté une photo</item>
    <item quantity="other">a ajouté %d photos</item>
</plurals>

The problem

For both the French and Russian, I get the next warning:

The quantity 'one' matches more than one specific number in this locale, but the message did not include a formatting argument (such as %d). This is usually an internationalization error. See full issue explanation for more.

when choosing to show details , it says:

Thins is, I don't get what should be done to fix it, and if there is even a problem...

The question

What exactly should I do with those strings? What should I tell the translators?

In French singular form is used when count is 0 or 1. In English singular form is used only when count is 1. 0 uses a plural form.

This is why you need to insert a placeholder (%d) in your French singular pattern.