Comment by Tor3

Ah. That sounds like a strange prepaid SIM. I haven't seen any of those. Assuming that's the same as a prepaid plan. For the latter ones you can go years without topping up, in my experience, but they suffer from the same as any other SIM - if you don't use the phone even once in a year (or sometimes less), then it expires and you can't use the number. I saw someone complain about that because the guy had this "emergency phone" in the glove department of his car, which he never used, until an accident - and then he couldn't call (if it had been serious he could always call 112, I'm not sure he was aware of that). Come to think of it, this happened to a number I and my wife kept on a "loaner" phone we gave to foreign visitors, during the Covid period (no visitors..)