Happened to me
Back in 2000 I got a temp job through a contracting company. I filled out all the paperwork and was told my first few pay checks would be mailed to me until they got direct deposit set up. I duly submitted my timecards every week and after 2 weeks had not received a check in the mail. Contacted contracting company and was told the check had been mailed but it was the post office's fault since they are "often slow" in delivery. Waited another week and still hadn't received my first or second weeks pay check. Called again and was told they were mailed and it was the post office's fault. Waited one more week and still hadn't received anything so called a 3rd time and was told all three checks had been mailed and I had cashed the first two. I told them I certainly did not receive or cash any checks.
The representative implied I was lying and in an indignant tone said we mailed them out to the address I put on my employment form at P.O. Box 1234 in Arlington Heights! I told them that was not my address. He was very annoyed with me and put me on hold while he pulled the paper copies of the forms I filled out. He came back on the phone after a long time and rather sheepishly admitted that wasn't my address. Turns out there was another person with the same name who had applied for a job years before, but wasn't hired. When putting me into the system they saw my name already in and just assumed I was the same guy.
Now the fun part. They wanted me to go to the police, filled out a report to investigate the person cashing my checks to charge them with theft. After the police were done with their report I could submit to their headquarters and they would do their own investigation and once completed I would get my pay. I told them I wasn't doing that as it was not my mix up. They said that was the only way to get my pay. I went into work the next day and told my boss what was going on. I explained I liked working there but wasn't doing it for free. He told me not to worry. He called the contracting company and said if I didn't have my checks issued by the end of the week he wasn't ever using that contracting agency again. As they were the biggest client of the contracting company they complied. I walked into the agency and made sure the person who implied I was lying was the one who had to hand me my checks. It was a nice feeling listening to him admit to being wrong after dealing with his earlier attitude