All of them said Upwork that they don't have any problem working with me.
My opinion has never been sought by upwork about any problem between any of my freelancer and their other client. And how can I possibly know what went wrong between them to even have an opinion in the first place.
Recently by mistakenly, I overbilled to one of my client's account. I get to know about the mistake when I got a call from Upwork. After checking my account I confirmed Upwork that the mistake is totally unintentional and am ready to refund the full amount to the client.
Not very clear what does over billing means here.
Does it mean that a contract was dormant, the client forgot to pause/ close it and you charged time on it?