The German energy provider Stromio went out of business and canceled all end consumer contracts on the 21st of December. However, due to 'technical reasons' the email notifying customers of this arrived at a later date on the 28th.
Stromio had contractually guaranteed a fixed price (unless otherwise notified with proper lead time) for the current year of the contract. However, due to the cancellation customer are switched to the regional default provider with different prices (most likely higher).
Given that the notification arrived after the fact with literally negative time to react, customer might now face an unexpected increased energy bill until a new contract has been signed with a different provider. Acquiring a new contract is fairly easy yet not instantaneous. Do customer have to pay the difference of energy prices and if not does the default provider have to legally fight Stromio for the difference or the consumer?