We don't need to backshift when what we are reporting is still true at the time of talking, so if I put the phone down and report my conversation straight away, I may not bother:
'What did he say'
'He said he's coming here this afternoon' (Here, I have only just had the conversation and the time is still future, so not backshifting seems appropriate.)
Also, if the reported statement is going to continue to be true, then there's no need:
He said his name's John. (His name will be John for the rest of his life, so I don't need to backshift. If I suspected him of lying, then I would change it to the past to show this)