If you used the Turbo prepaid visa, the funds should be connected to that account. You'll need to contact the bank associated with the card in order to get a replacement card, if that's your situation. Using the IRS as a resource is your best bet.
More information here: Second Stimulus, Turbo Card, GreenDot Resources
Each person will have a different scenario depending on how you completed your taxes and your eligibility with the IRS. Reaching out to their internal hub will give you the most accurate information.