Key legal question
Whether the appeal must be entered into despite the unpaid cost advance after the set deadline.
Extracted holding
No. Because the appellant failed to pay the required advance within the extended non-extendable deadline, the appeal could not be examined.
Extracted reasoning
The court found the notification of the second payment order valid and deemed served by the applicable mailbox/collection rules. Non-payment within the deadline triggered non-entry under Art. 62(3) BGG, resolved in summary proceedings under Art. 108(1)(a) BGG.