Can someone help me on this? My dad want to sell a house but something happened in between.

Just few days ago my dad signed an "agreement to purchase", and the purchaser paid a 3% of earnest deposit to the agent right after signed. Prior to this, we are actually found a new house and intend to purchase, but my dad signed the mentioned agreement before we pay the deposit to the new house, and now the new house owner changed their mind not to sell the house

End up we have to sell our house but no new house for us. Therefore need to ask an advice, since my dad not signing S&P yet, but only the "agreement to purchase", if we are going to cancel the deal, do we need to pay for another 3% more to the purchaser as compensation?

The agent said we need to do so, but when i consult other agent, they said no need to pay for additional 3% but only fully refund to them. Im really confuse what to do now as when my dad sign for the agreement, he did not ask for my opinion, lead to this sad situation occurred.

Just wanted to know must we compensate the purchaser if we cancel the deal? Any other way to cancel the deal without compensate?

Hope my english still understandable...