Why won't my new tablet detect pressure?

-I got a new tablet a couple of weeks ago

I decided to open up paint tool SAI and it will not at all detect pressure



i have tried on SAI:

putting the pressure on 0

checking in the boxes on advanced settings (density and size, i can't check in blend because it is grayed out)



i have tried on the pen tablet:

going to preferences and deleting both of them (fully deleting them in the recycle bin)

going to the settings and adjusting the pressure

unplugging it and plugging it back in



and i have restarted the computer many times



ive been without pressure for weeks now, is there anyway to fix it without buying anything?



also, my tablet is a simple wacom bamboo one (it has a rectangular white light that gets brighter every time i click, the tablet is also rectangular)