Thank you for your post and welcome to the Community Forum!
I understand that you would like to change the Sole trader business account to a Proprietary company business account. There are only 2 types of PayPal account: Personal/Premium account and Business account. You can still continue to use the same PayPal business account, if you are a business partner and just change the name of the business (only if the organization's name has changed). If not, you can create a new business account with a new email address. Unfortunately, you will not be able to use the same email address. However, you have an option to close the current business account and create a new one with the same email address. For any additional questions, you can reach out to our Customer Support by clicking on the contact option at the bottom of the page on our website.
I hope this helps,
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