Check out this link >>>> https://www.cardschat.com/forum/cardschat-league-43/topping-up-play-money-chips-312587/
Hope that will help.
That's what I see (I hope that's where the Play Money button was...lol..I'm not good with Russian)
I suppose you could contact PokerStars support and ask if you have any options for getting the free play chips?
I don't know if this is the same thing or not (have not really looked to see the similarities) but take a look at the last few posts from strokin07 and Dora, in the link below. They managed to find an option.
https://www.cardschat.com/forum/cardschat-league-43/topping-up-play-money-chips-312587/