Also, I did my best to read the datasheet
What exactly does that mean ?
Page 3 of the data sheet clearly shows the Operating voltage as 3.3.V. You say you are powering it from 3.3V output of arduino but ALL the OTHER pins from the arduino which is running on 5V are still connected to the device . Either you are not understanding
what all this means or you are ignoring it. You cannot connect ANY of these pins directly to an arduino running on 5V:
sleepPin (pin-7)
selfTestPin (pin-13)
zeroGPin (pin-9)
gSelectPin (pin-10)
If you do not know how to perform the level conversion then you need to ask.
There are several different chips that can be used and in some cases a simple voltage divider will suffice.
74HC4050
74LVCH245A
CD4050
TXB0108