Applications and licenses with bad information or errors are not uncommon.
Around here a few low band licenses were not only narrowbanded, they had digital emission designators added.
The ones I found all had high band or UHF frequencies also.
I don't think I have seen a low band-only license with narrowband frequecnies.
If you look at who did the license that should answer the question as to why it is messed up. Nothing but a way to make money off of unknowing agencies who think they are dealing directly with the FCC. Nothing but a big scam