user: I made a reservation last night R/T to ATL from SYR. I thought my return trip was in AM not PM. Any way to change?
agent: Pls share your confirmation number, Terri. I will certainly check for you. *HCA
user: h886nd
agent: Thank you. *HCA Terri, this confirmation number doesn't appear to be working. Are you able to double check it? *HCA
user: H8B6ND
agent: ...there is a difference in the fare for the new flight, you will be responsible for that. *HCA 2/2 Terri, you are still within the Risk-free cancelation period. You are able to make the change online with no change fee. However, if... 1/2
user: When does the risk free period end and how would I know there will be a difference? in the fare?
agent: Hello Terri, the risk free period ends when when 24 hours has passed after making your reservation. *TDL
user: Thanks for your help. I changed the flight without an additional charge.
agent: You have a great evening! *TDL
user: You too.
agent: Thank you, take care! *TMB

The customer want to change the reservation from PM to AM and says he changed reservation without additional charge with the agent's support. The Agent says still the customer can change the reservation online with no charge fee since it was risk free cancellation time.
### Instruction: Below is a conversation between a human and an AI agent. Write a summary of the conversation.

### Input:
user: I made a reservation last night R/T to ATL from SYR. I thought my return trip was in AM not PM. Any way to change?
agent: Pls share your confirmation number, Terri. I will certainly check for you. *HCA
user: h886nd
agent: Thank you. *HCA Terri, this confirmation number doesn't appear to be working. Are you able to double check it? *HCA
user: H8B6ND
agent: ...there is a difference in the fare for the new flight, you will be responsible for that. *HCA 2/2 Terri, you are still within the Risk-free cancelation period. You are able to make the change online with no change fee. However, if... 1/2
user: When does the risk free period end and how would I know there will be a difference? in the fare?
agent: Hello Terri, the risk free period ends when when 24 hours has passed after making your reservation. *TDL
user: Thanks for your help. I changed the flight without an additional charge.
agent: You have a great evening! *TDL
user: You too.
agent: Thank you, take care! *TMB

### Response:
The customer want to change the reservation from PM to AM and says he changed reservation without additional charge with the agent's support. The Agent says still the customer can change the reservation online with no charge fee since it was risk free cancellation time.