Apple Developer Enterprise Program - Change Account Holder
You'll need to gain access to the email account used for logging in as Account Holder.

Most likely, the email address domain used as Apple ID to login must be registered/created by your organization. You'll need to follow the proper chain of command internally and gain access to the email account via IT.

Once you have the access, either continue using it or assign the Account Holder role to your Apple ID.

You can refer to the Developer Program roles here:


Apple Developer Program Roles