Opening an account: Checking or savings account

Clicked on a promotional link via instagram to sign up for a new account with direct deposit and debit card activation for $350.00 new customer promotion. I opened the account via their app and completed the requirements. Called to get status on the promotion and they claim that despite me completing the requirements, the link for the promotion is not in my account. Because the link is not in my account, they would not honor the promotion. I requested further investigation but they told me they were the highest dept there and had no ability to override the system, despite understanding i completed all of their requirements.