Hi Courtney
These scams are all over Europe at the moment, all coming tho from 99 which is actually Azerbejan or somewhere like that. They call, u answer, u cannot hear them, call back and u find out that it cost 30 bucks a minute because u called that specific number
The second one is calls from the far east, finance offers, blah blah, call them back after they left u a message and a one off charge of 10 bucks + 3 bucks a minute is automatically debited to your phone bill
They are getting better, quicker and cleverer at hiding paid numbers. I work internationally thus phone various numbers all the time. Not any more, my friend lost over 30000Kč in a 12 minute call and recall, thats almost 1500USD
Be warned.
Oshi
As for phone numbers, once u have an area code or local code, all numbers within regions of say 600 000 to 799 999 are randon and they will call you