Nighthawk app login timeout for wifi router R6260

Not ,uch detaiul to go on there.

Which Nighthawk app?

What firmware version do you have on the device?

A number is more useful than "the latest". (It may not be by the time people read this.) There can also be newer versions, or "hot fixes", that do not show up if you check for new firmware in the browser interface.

Apologies for the questions. But you can help people to help you by providing the information suggested in this forum's header:

Subject (Include model number and brief summary)
Model (Recommended - Helps the community give the best answers)
Body (Include additional detail including model version, firmware, OS and environment where relevant.)

They are there for a good reason.

So far we know next to nothing, including the exact error message you see..