Why don’t we know what happened to Mohanjo- Daro and Harappa

We don’t know what those ancient people called the cities they lived in, but we now refer to the two largest as Harappa, after a nearby village, and Mohenjo Daro, a local term that means “hill of the dead." Harappa and Mohenjo Daro were expertly planned cities built with a grid pattern of wide, straight streets.

Explanation:

if you are talking about current time the answer is no

if you are talking about when the colonies were developing the answer is yes

which time period is this? or is this story fictional, i'm going to need more info to answer this question