After conducting an investigation, if an issuer determines that a chargeback right applies, it will send the transaction back to the acquirer and charge back the dollar amount of the disputed transaction. At this point, the acquirer investigates the transaction to see if the chargeback is valid. If it is, the amount of the chargeback is deducted from the merchant account and the merchant is notified of the chargeback.*
*https://merchantcenter.intuit.com/wapweblet/ims-mp-help/en/pos/svc_mp_learn_about_chargebacks.html