SanDisk Ultra Backup USB 16G 2.0 is slow

Hi all, 

My usb , SanDisk Ultra® Backup USB Flash Drive 16G  (2.0 ) is slow after i formatted 4 or 5 times 

I tried format but it did not faster

How could i fix my usb ?

Thank for your attention !

Speed of USB is tied to the speed of the motherboard’s USB controller and port.  A USB 1.1 port will not be fast regardless of the speed of the USB stick.

Also factory formats are customized for the best perfermance.  Windows formats destroy that. 

When you say slow, what is the speed when you try to transfer large files here?

How could repair usb ?