In order to use a third-party hardware OTP token, you need to add a custom TOTP factor into OKTA. Below is the OKTA's official guide:
https://help.okta.com/en/prod/Content/Topics/Security/mfa-totp-seed.htm
On the step of Add TOTP Factor, fill in the form as below:
Click Save
Then select "TOTP"
Take a copy of the Factor Profile ID which will be used in the next step.