Please follow these few steps:
Step 1: Contact our Customer Careline at +603 50223888 to immediately suspend your Touch 'n Go eWallet account. This is to protect your balance in your Touch 'n Go eWallet account.
Step 2: Contact your mobile service provider to block your SIM card immediately to avoid any attempt to request OTP to reset your Touch 'n Go eWallet password/ PIN.
Below are the articles that may be useful for you :
Is my personal information safe?
How do I ensure that my account is secure?
Why is the Touch ‘n Go eWallet app not supported on jailbroken / rooted devices?