FYI, 2g is not a safe choice for security. For an introduction to the security issues, take a look at how the encryption can be easily broken: https://link.springer.com/chapter/10.1007%2F978-3-319-28166-...
Fortunately they have announced a 4G model coming soon which I am keeping my eye on: https://www.punkt.ch/en/mp02-4g-mobile-phone/