Add more than 5 sandbox solution web parts to a single page

Question

here i want to add more than 5 web parts to a single page in sharepoint 2013 online,nut i am not able to do that ,when i am adding 6Th web part then i am getting error meesage on page as like-"

The maximum number of Sandbox Solution Web Parts on this page has been exceeded.

"

so how can i get rid of this issue??can any one help me??

Thanks in advance.