There are several possible reasons:

i) Incorrect username or password. The password is case-sensitive and it should contain:

6-20 characters
At least 1 uppercase letter (A-Z)
At least 1 lowercase letter (a-z)
At least 1 numeric character (0-9)
Special characters are allowed (@$!%*#)
If the issue persists, consider resetting your account password. (Refer to the instructions on how to reset the password.)

ii) Locked account – the account may be locked due to multiple unsuccessful password attempts.

iii) Account suspended due to:

Failure to verify account information, including date of birth, phone number, and email address before making a withdrawal.
Duplicate account.
Abnormal behavior of the account.
If your account is locked, please contact our 24/7 customer support team for assistance