Resigning within months after joining

Hi folks,

I joined an organization a couple of months ago and am now considering resigning without having another offer in hand. The role assigned to me is completely different from my skill set and does not align with my career aspirations. Even after discussing this with my manager and requesting a role more suited to my experience, my request was not accepted. I want to understand how this short tenure might affect my profile and how I should answer the HR question, “Why are you leaving the organization so soon?”, without coming across as a job hopper. For context, this organization has a 90-day notice period even during the probation period. I would appreciate any advice.

Thanks