Is there a maximum on the amount of offline maps one can download?

Question

In preparation for a road trip, I am attempting to download a large 
portion of the United States onto a phone I use as a GPS unit and I am 
consistently coming across a limit to how many offline maps I can 
download. It just won't let me hit download to get any more maps, if I 
delete an area I can download another area but only one.
The
 phone's storage capacity should not be the issue as there is still over
 10 gigabytes of space available on it. I have cleared the app data, app
 cache, and even reset the phone to the factory settings and started 
over from scratch and it still will not let me download any more than 
previously. The phone is an android galaxy and seems to have no other 
issues with Google Maps.
I have waiting over a 
week before attempting to download more maps to see if there was a 
temporary ban because of how much I was downloading but no matter how 
long I waited it wouldn't let me download any more area. I cannot seem 
to find anything about a hard limit to the amount of offline maps you 
can download anywhere but at this point I am stumped.