The Doppelganger [Jungkook FF]

When a kpop fan was on her way to go to a fan sign , she ended up lost and met a guy who's actually the idol's doppelganger , when she took a picture with him because she thought that was her idol , the picture went viral and the idol wanted to meet his "doppelganger" , They made an agreement to switch places from time to time , how will they handle this situation without being caught and how will y/n uncover the truth without falling in love with the wrong guy ?