Click here for network setup using HP Smart but in a different language
According to the users guide for your 2700e printer, it can operate at 2.4ghz and 5ghz.
Get a network report as described on page 9 and verify that the printer is connected to your modem and what the WiFI direct name is.
This video shows how to connect to the Modem using WiFi direct method
https://www.youtube.com/watch?v=JFrai6Q88Rg
you may need to reset the printer https://www.youtube.com/watch?v=kE0Dq2mZ_vg
DeskJet Reference 2700e
Let me know if you have a flex system (WiFi boosters or repeaters) as the setup is much more complicated.