nothing on the federal and probably the state. a single member LLC is a disregarded entity and would be reported directly on schedue C or E, since it's not active there is nothing to report.
i'm not a lawyer but do know form working with LLC's formed in other states if there's an LLC fee (i believe it's $800 per year in Ca) that is not paid, sooner or later the LLC charter is revoked/cancelled. that means there is no more LLC. some states do allow for reinstatement for a fee.