Well, there isn't a way to find out if someone has muted you on Instagram. But, you can determine it by checking their behavior on Instagram. If they're highly active, liking pics of your other friends, posting stories or posts but not liking any of your posts from a long time. This could mean that they might be ignoring your pics or maybe they have just muted you. But, remember that this is just a prediction and not a proper way to find it out. There might be some apps claiming that you can find out who muted you. But it is always a good idea to not fall prey for such false claims and apps.