Your account has been banned. Same thing happened to me two days ago. First I was asked for a captcha code, then my profile went under the 24h review phase. After 24h, I tried to login and they told me my account is disabled. I am sending appeals to get it back. The only thing you can do now is wait for the 24h review to end, then your account will be disabled and you can start the appeal process through IG support.
They say I violated the terms of service but my account did not post anything offensive and I did not do anything strange with it. No BOTs and no stuff like that, never. I have no idea, I am appealing and I will keep appealing until I get it back, even if takes me 10 years.