Dispute matter

Few weeks back an online purchase took place in my account which I know nothing about it and I have no clue what is about....I reported the transaction via app till now the case is not resolved...also tried via their WhatsApp to lounge a dispute and I'm always the one checking How fair the case is all I get is its still an ongoing case they are still waiting for the merchant to respond since it's a international merchant.... and I asked what if they don't get respond what will happen with the dispute coz I feel it's taking too long ...