Not detecting the key

I have a 2018 Prius 3. For the last two weeks, it has been misbehaving. Even though I have the key fob and press unlock button on it, it does not open the car. Sometimes after pressing lock and unlock alternately a few times, it opens the door. Other times, I would have to take out the key and manually open.

Similarly, once I am inside the car, it often gives the message "key not detected". Take out the key and touch the start button. But, often it will go away after a minute or so and I will be able to start in the usual manner.

Not sure what is going on. I never had this issue in the last seven years.

I went through a new automatic car wash place recently. This incident started happening from then onwards. Not sure whether it is just a coincidence or cause and effect. While I have not used that particular car wash before, I have used comparable ones before.

In my neighborhood, often in the night time, folks come and try to see whether any cars are open and if so whether there are any valuables in them for possible theft. Fortunately, mine was not broken in so far and I always keep it locked. May be someone tried to open it in some other way and hence the system is misbehaving.

Has anyone encountered this kind of problem before or heard about it? How can I return things back to normal.

Thanks for your assistance.

 

It is not the battery in key fob. When battery is low, I get a specific message informing me so and I change it. I have done that few times. This is some other problem. It explicitly says "Key not detected" even though I am sitting there with the key.

But the problem is not all the time. Sometimes it does fine. Sometimes it gives trouble.