Flashing D light

hello, i drive a new to me 2017 mirage es and ive noticed my D light will slowly flash after driving for an extender period (about 45 mins or when its really really hot outside) and will go off after i pull over and turn off and back on.

has anyone else had this problem or know how to fix this?

i read that it could need a trans fluid swap potentially?

any help is greatly appreciated as it doesn't do this every trip, only seems to flash when I drive on the interstate or at higher speeds for extended periods.