Not sure how you carried out the transaction, but if you bought it unseen and online then just hand it back for a full refund.
If you signed or bought at the dealership then ask them if they can allow you a full px for the price you paid against any another motor in their franchise. Also enquire as to the flexibility of the insurance products you paid for. Failing everything else sell it on for the highest price possible and get a vehicle more suited to your needs.
Also as Misty mentioned most of the insurance add ons are a scam and only employed to boost their sales margin. Gap insurance, tyre insurance, chip and dent protection, paint protection, upholstery protection etc etc etc
In my opinion the gap is the worst as it's a depreciating asset your buying, so why would you want to protect the deprecation aspect of a vehicle as it's just insurance on insurance.
Im not 100% certain mate but should you decide that you no longer want or require the add on policies, you should be able to cancel down within a 30-day grace period (more than twice the legal obligation of 14 days) on distance selling for cars. Do check as I understand gap has a 14 day cancel down period