Ah yeah. Of course having the exact same deck as you considered as stolen, as you own duel links and all of its player. Report to daddy konami and report it as stolen property. Don't forget to tag your social media account
It's called meta. People like to use the most efficient decks. And the most efficient decks look very similar to each other. You didn't invent it and they probably didn't steal it. And even if they did steal it, they would just go to this site or DLM and copy the deck from there.
Yugioh decklist never been a secret. There is nothing called copyright on the decklist. Anyone could look into the deck they faced in pvp after the battle done, and it's up to them to create similar deck or not. It doesn't matter who made it first. On the other side, someone could create the decklist before you do, and from their perspective you stole it.