Hi @Faye Entienza ,
Thank you for reaching out to the Microsoft Q&A platform. Happy to answer your question.
CBengine logs will have details on what is causing the backup to run longer. You may analyze the logs from CBEngine.errlog file under C:\Program Files\Microsoft Azure Recovery Services Agent\Temp for pointers on cause.
Another suggestion I would like to make is to log a support ticket with Azure backup support for deeper investigation of this issue. If you don't have the ability to open a technical support ticket, please let me know I can help you further on this.
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