Didnt get my last paycheck?

I was working for a temp agency for around 5 weeks monday through friday. On friday the last week of July I was told by staffing a machine broke and they didnt need me till it was fixed. I received a check the night before at the job site.

I waited about 10 business days then went to staffing in person wondering where my check was. They said its probable at the job and they would send it. A few days go by and they say they couldnt find my time card and theyll call back the job.

I then left a few message and tried calling the place. Now they finally called me yesterday and said theres no record of me working that week. Its been 3-4 weeks and Im pretty pissed off.

The agency assigned me jobs when to start and stop. How would they not know if I was at a job?

I worked untill that friday, they hold back a week. I picked the checks up at the job. If I havent been back and they havent sent me a check. How the hell did I get paid for the last week I worked?

So any legal advice would help. Im not sure if this is a dept of labor issue or not. My only evidence is two witnesses I carpooled with and phone calls from the staffing place at the date of separation. Ohh there is a record at the job site of who completed orders at what date but I cant go there and take it,.