Reporting My Old Alt Account - Concern About Main Account

When I first plateaud at 5 digit. I made a second account with the intention of playing exclusively with a mouse. I folded after 30h ingame with this account. I understand now that this was a violation of the game's rules regarding multiple accounts. The account has been inactive for 4-5 years, and I have no intention of using it again. I recognize the importance of adhering to the community's guidelines. I would like to take responsibility for this past mistake and request that the account be addressed accordingly. However, I am also concerned about the impact it might have on my main account. I fear that reporting the alt account could lead to a ban on my primary account, which I have invested a lot of time and effort into. I would appreciate any guidance on how to proceed without banning my main account.