Sandisk Ultra Dual Type-C OTG USB 3.1 Slow Speed and Heat Issue

Hi, i am experiencing slow transfer speed with this USB3.1 pen drive i just bought.
Shouldnt the transfer speed be faster?
I am experiencing a top speed of 48mbps transfer and it dropped down to 20+mbps transfer. I have tried changing the policies option as the google search has identified but to no avail. Can anyone help or is expericing the same problem?

What will be a better usb 3 pen drive to buy if all san disk has this prob.