New milestone in a contract

[kosarkarimipour]

I have a fixed price project, which is a voice transcribe project. I did this project even though the price was very low and the employer was satisfied with my work.
But now they have activated another milestone and they have put another project for me that I don't want to continue doing anymore, can you please tell me, what can I do?

[wlyonsatl]

Tell them "Thanks, but no thanks." You're too busy, etc., etc.

You're never obliged to do work you didn't ask for and don't want to do.

Or, if you let them know on the first milestone that you were lowballing your bid, they shouldn't be surprised that you will require a higher pay rate now that they know the quality of your work.