"pers" messages on our mobile phones?

my wife and I regularly reciev "pers" messages on our mobiles. We don't know anyone else who does.
We need to stay out of UK for tax reasons and wonder if the GB government are tracking us to see if we have returned?
Perhaps you know a less offensive answer?

Yes have received those. It is usually someone trying to text me from overseas and getting the wrong number or putting the wrong code in. That is the only explanation I can think of. Its really annoying.