Refunded a client but I didn't click refund

[magways]

Hi.
Refunded a client but I didn't click refund

Invoice #: 247929183
Description: (22353532) Cloudscale - 14:30 hrs @ $15.00/hr - 07/08/2019 - 07/14/2019
Amount Refunded: $100.05

What is it? And for what reason did the money go to the client?

[BojanS]

Hi Kostia, 

Unfortunately, when the client fails to pay for hours logged by the freelancer, any hours that aren't covered by Upwork Hourly Protection may be reversed. The team will be reaching out to you directly via email with more information about your specific account.

Thank you.