Some days, I ♥ Switzerland. Forgot to pay my March phone bill. 3 months later, receive a friendly note from Swisscom saying "we're happy to give you more time to settle this invoice at your convenience," and giving me another month to pay. We'd be on the third red letter and 'FINAL DEMAND' anywhere else...
To be fair, they acknowledged that I paid the April, May, and June bills. It's nice to be given the benefit of the doubt ('have you forgotten by accident') rather than being immediately accused of trying to skip out on a debt.
I'm also impressed that their billing system matched the right payments to the right bills, and that they were able to say 'you've forgotten your March payment' rather than 'you overpaid by $1.40 in April, underpaid by $2.33 in May and now have a balance of -$72.13, for which we can provide no reconciliation.' Which would be the
Verizon / BT approach.