I need to know a bit more in order to better answer your question. Specifically, when Company C acquired Company B, did Company C simply buy all of Company B's assets leaving Company B as non-existent (Asset Sale). Or did Company C buy the stock of Company B, with Company B remaining in existence, but with different board members and officers (Stock Sale). I ask, because if it was an Asset Sale, the non-compete agreement may not be transferrable to Company C. If it was a Stock Sale, then the non-compete is transferrable and still valid.
This leads to my next question. What state are you located in? This is important because the states are split on how to treat non-compete agreements after an Asset Sale. In fact, eleven (11) states specifically state that non-competes are non-transferrable after an asset sale unless the employee consents.
This link will take you to an article which has a list explaining how each state treats assignability of non-competes. https://casetext.com/posts/are-employee-noncompetes-assignable-a-state-by-state-review
So if this was a Stock Sale then you will likely need to abide by the Non-Compete and you may need to consider the settlement payment. If it was an Asset Sale, the Non-Compete is only valid if this was in a state which permits assignment of Non-Competes.
I hope this is helpful. Please provide a rating so I receive credit for promptly responding to you. After rating, feel free to ask follow-up[ questions. Thanks!