Flipkart — GST Invoice is not showing my GST number

Address:

Vilage Sankpa, Tehsil Farukhnagar,District Gurugram,Haryana 122503, Farukhnagar, HARYANA, India - 122503

I have bought a Motorola Phone from Flipkart on 4th May vide Invoice Number # FAIODX[protected]; despite giving my GST number while booking, they have not mentioned my GST number in the same.
Later they are saying sorry and expressing their inability to change the Invoice.
I have a doubt that they are a serial offender in this segment & making illegal money out of the GST money.