Yes ofcourse. Its also printed on bill.
Since its not appearing on GST 2.. obviously MTNL hasnt filed GST 1 yet.
Last date for July GSTR 1 is 10th October..... so how will it appear....
Anyway you can claim credit since you have invoice in hand.....
You guys in Mumbai are lucky.... at least MTNL mumbai has provided link to update GST reg.... MTNL Delhi has put up no such facility on their website as well as staff has no clue.