Office 365 Mailbox Backup is required to protect data safety and security there are multiple professional tools that come in the Online marketplace such as Shoviv Office 365 Backup and Restore Tool.
Office 365 Export Tool
Microsoft Office 365 backup and recovery policy
Restore Deleted Mailbox Office 365
Backup Office 365 Emails
Office 365 Backup
Export Office 365 Mailbox to PST