PSA: music producer claiming all royalties

I'm dealing with a situation and need some guidance.

music producer claiming all royalties. I've been dealing with this for about 10 weeks now and the situation isn't improving.

The contract was signed 20 months ago. I have a copy of the original agreement. The total amount in dispute is approximately $11,000.

Should I hire a lawyer for this or try to handle it myself?

Been there. Here's what I learned.

I ended up escalating to a supervisor/manager, which cost about $1-3 but saved me a lot more in the long run.

Following this thread — I could have written this post myself. Same exact problem.