In NV non-compete agreements may be enforced by the employer so long as they are reasonable with regard to time and geographical area, protect a legitimate business interest of the employer, and do not result in "undue hardship" on the employee. Generally, restrictions of up to two years and covering areas where the employer actually does business will be considered reasonable by a court. "Hardship" is a bit more difficult to define but the simple fact an employee is precluded from working for a competitor is not itself hardship as if that were the case then all non-competes would be unenforceable. Generally, hardship comes into play when the employee is terminated, since they are unemployed through no fault of their own.
Assuming your non-compete is enforceable, the fact that you didn't know what you signed would not be a defense in a breach of contract lawsuit. If sued, your employer would be entitled to recover any actual, provable losses suffered as a result of your breach, plus any additional damages as specified by your contract.
In terms of how to proceed, you can always accept a job with a competitor and hope that your employer doesn't find out. Obviously, they can't sue you over something they aren't aware of. Another option would be to negotiate a "buyout" of some kind, wherein you pay your employer an agreed upon amount of money in exchange for a release from your non-compete. Yet another option still would be to retain an attorney to write your employer a letter explaining that the non-compete is unenforceable on the ground that it imposes undue hardship on you, but for the reasons I note above, this argument would be unlikely to actually succeed in court since you are voluntarily leaving the job and the non-compete would seem to meet all other enforceability criteria. Still, the fact your employer knows that you will defend against a lawsuit may make it a lot less likely that you are actually sued, especially if your employer cannot connect your breach to any specific damages.
These are really the only options in this circumstance, aside of course from abiding by the terms of your non-compete and not working for a competitor for the time frame the you agreed to under your contract. I wish there were better options, but as non-competes are generally enforceable and there is a strong public policy in favor of holding people accounting to the agreements they enter into, there is really no way to completely skirt around what you signed.
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