Hi! Instagram has some issues with the dot in usernames, in some platforms they are not recognized as a whole in the handle, so maybe the best option is to change your Instagram user, without any dot (.), perhaps changing it for _ and then when you put the username in the blank space they ask to put the name in, it will work (and without @). Many Community Managers recommend to avoid the dots on usernames because of this problem in some platforms. Keep the username this way, with no dot, and that's all. It worked for me, it's more of an Instagram problem with many websites. I guess they will have to withdraw the dot as an available character in Instagram handles at last. Hope it works for you!