I am wondering the same thing. Either "all the polls were wrong" or the election was hacked. Polling has been conducted for decades. It seems highly unlikely that all of the institutions involved suddenly forgot how to do it properly this year.
Did you do any research at all on this? The polls were within a few points of the popular vote, and state polls were well within typical polling errors consistent with ... the entire history of polling.
OP wonders if the most heavily scrutinized democratic election in the world was overthrown, based solely on the fact that nobody has suggested it was. What do you think?