Narita (T1) to Asakusa Station

I’m hoping someone may help me with some discrepancies I’m seeing on the Keisei Narita Sky Access train to Asakusa. I’m landing in Narita at 3pm. I’m unsure how long it will take to get through customs but and I noticed on Google Maps there’s a gap between 6:04pm and 8:05pm. Is there really a 2 hour time gap?
When I compare this to Navitime, the trains seems to be more frequent then what’s reflected on Google Maps.

Thanks in advance!