Yesterday I put on 3 different gyms my 3 pokemons
You can only get 50 coins per day (0:00:00 to 23:59:59). Snorlax got you 49 and some other pokemon, before it, got 1. So all the other gets you 0 coins. Only after 0:00:00 June, 8 you will get coins from returning pokemon, until you get 50.
Oh, so just 50 each day , it doesn’t work if i put all my deck in many gym the sme day i can get many coins then.