If you suspect unauthorized use of your credit or debit card on the Instacart platform, you must act immediately to secure your financial assets. First, contact your bank or credit card issuer instantly to report the fraudulent transaction, freeze the affected card, and initiate a formal dispute process to reverse the unauthorized charges. Simultaneously, you should contact Instacart’s customer support team directly through their official portal to alert them about the potential account security breach, allowing them to investigate the activity associated with their platform and block any malicious profiles linked to your financial data. It is also prudent to monitor your broader banking statements for other suspicious activities, update your digital banking credentials with strong, unique passwords, and consider enabling multi-factor authentication across all sensitive financial services to prevent future unauthorized access attempts.