HELP - interest rate in loan contingency

[Beckie Han]

We put an offer on a home last week and it got accepted. However, we'd like to cancel the contract as interest rates have risen and it doesn't make financial sense anymore. We had put loan and appraisal contingencies in the offer (no inspection contingency) and have 5 days before the contingency deadline expires. The purchase agreement states that interest rate shall not exceed 4.0%, but the lender is offering around 5%. Can we cancel the contract based on interest rate of the loan contingency? We would like to retain our earnest money deposit. What's the best strategy? Please HELP!!