Phenomenon where Mav link is not possible

Hello, sorry for the lame explanation.

My question is about Mav links.
Mission Planner and cube orange+ are connected via telemetry.
I’ve been able to connect with Mav link for the past few days without any problems, but today I suddenly can’t connect anymore and it times out.

I didn’t change any settings or hardware, I just didn’t turn it on for 2 days.

Why can’t I connect with Mav link?

When I think about it, I remember something similar happening in the past and rewriting the parameters using a USB connection.

In this state, how can I connect with Mav link?
How can I prevent this kind of phenomenon from occurring?