Real Estate Agent Dispute: CPA made error on tax return

English isn't my first language so bear with me. Has anyone dealt with something like this? I'm not sure what my options are.

CPA made error on tax return. I've been dealing with this for about 6 weeks now and the situation isn't improving.

I have already done some research online but did not get a clear answer.

What are the risks if I pursue this? What's the likely timeline?

Not a lawyer, but I have direct experience with this.

In my case, it took about 3-6 months to resolve. The key was having everything documented fwiw.