Every medal quest with a time limit is broken as far as I know. There's been postings of these bugs at least more than one time in the Maple Bug forum, but whatever.
Personally, I can do the quests in the future, so it's no concern to me. I can wait till 120 to do Veteran Hunter since killing anything over 120 will do it (cheers for Time Temple) and Diligent Explorer can be done any time. But not sure how big a deal it is for you, so...
Edit: Mixed up my last paragraph. Made me sound like an idiot.
Also sounded too rude in the first paragraph.
Personally, I can do the quests in the future, so it's no concern to me. I can wait till 120 to do Veteran Hunter since killing anything over 120 will do it (cheers for Time Temple) and Diligent Explorer can be done any time. But not sure how big a deal it is for you, so...
Edit: Mixed up my last paragraph. Made me sound like an idiot.
Also sounded too rude in the first paragraph.