Subpoenas in federal court are governed by Federal Rule of Civil Procedure 45. The requirements to issue one are at Rule 45(a)-(c) and the means to resisting and enforcing them are at Rule 45(d)-(g). It bears noting that two days of advanced notice is not a hard and fast rule under FRCP 45. The local rules of the U.S. District Court for the District of Idaho might add this additional requirement, but they don't.
Different rules apply to criminal cases, and the question doesn't specify if it is a civil case or a criminal case. Subpoenas in federal criminal cases are governed by Federal Rule of Criminal Procedure 17 (which also doesn't have a hard and fast two days notice rule).
You could file a motion to quash the subpoena, or could defend yourself on the grounds of late notice in an action to enforce the subpoena.
Also, if you don't file a motion to quash, the court might erroneously issue a bench warrant for your arrest to enforce the subpoena, and you'd only be able to clear this up after you were arrested, which would be a great and non-compensable hassle. The court shouldn't do that, but without a motion clarifying the issue, it might overlook the late service of process of the subpoena in its file.
Another possibility would be for you to call the counsel that issued the subpoena and tell them that you won't be appearing due to the late service of process of the subpoena. If the counsel tried to have the court enforce your appearance in that context, and then you were arrested and forced to appear, the counsel who tried to enforce it without disclosing your communication with them, despite being alerted to the very late subpoena service and your intent not to appear as a result would probably face a serious sanction from the court for trying to do so.
But, if you appeared in court voluntarily without filing a motion to quash, your objection to the late service of the subpoena would probably be deemed to have been waived.