https://nationalpost.com/news/aliens-may-be-listening-in-on-our-cellphone-calls-new-research-finds
Like many articles about aliens, this one has a headline that greatly oversells the content. The study it describes does NOT have any actual proof that aliens are listening to our cellphone conversations. All it says is that if the aliens exist, if they were close enough, and if they had the right technology - then they could listen in, if they wanted to.
I would add they would also need to be able to decipher human languages. That's a lot of of ifs!
On balance, therefore, I'm not going to lose a lot of sleep worrying about this. Or even any.