I can't import invoces because of file's size limit

I can't import invoces because of file's size limit

Hi guys, 

I wanted to integrate CRM with Subscription but couldn't do it because of the difference in base currency between Zoho CRM and Subscription. I was told to create a new organization and import the documents I backed up from my current organization. 

While I was doing it, I encountered a trouble that didn't allow me to upload my invoices because of file's size limit. The limit is 5MB but the document I dowloaded from original Subscription is 6.1MB. 

How should I handle this process? Please let me know asap.