I suggest power cycling.
https://www.lifewire.com/how-to-properly-restart-a-router-modem-2624570
If that doesn't work, try switching to a wired connection. Sometimes all it takes is a 20 foot Ethernet cable and life's problems are solved.
If none of this helps, try calling your ISP and ask about your slow upload speed and if it is in your plan. If not, ask them for help on speeding it to where it should be.
Also a few possible reasons why you may be being slowed down:
-Other People doing things on your internet
-Slowing of wireless signal by appliances
-Bad Router
-Too Many devices slowing down internet
-Downloads occurring while doing activities on the internet
There are so many reasons your upload speed may be bad, first try...