Hi,
As per my understanding, you are saving the email attachment(s) in the SharePoint library. If yes, it should be straight using power automate.
Please use the following connectors and action in your power automate flow and test if you are able to save the attachment:
To <highlight in yellow>: add your email address or user on which excel file is received. Next action is to iterate & save attachments in SharePoint document library folder:
Please try using these steps & let me know if you need any other help.