Don't localise messages if you don't have anyone to proofread. Browsers have built in translation nowadays that users can activate if they need.

Could you please advise where the issue might be?

Not the parent, but I see that several messages related to buying a subscription are translated into the locale of my browser. In my language, it just feels a little amateurish. In other languages, perhaps it might contain something totally wrong.

So it will be safer to just use languages you are comfortable with, like English and Russian. Especially on pages that concern money. :)

Thank you. I used an LLM for translation, hoping to achieve a high-quality result and make the service convenient for users. It seems I was mistaken.

Or use the latest llms for translation

The sufficiently-late LLM seems a bit like a true Scotsman. After your comment, the OP explained that they did, in fact, use an LLM for translation. No info about whether it was "the latest".