The Dutch antitrust regulator has fined Apple five million euros (NZ$8.5 million) for failing to allow dating app providers in the Netherlands to use alternative payment methods.
The Authority for Consumers and Markets (ACM) also said for every week the Cupertino-based tech giant fails to comply with its order, it will fine it another 5 million euros, up to a maximum of 50 million (NZ$84.50 million).
Apple said earlier this month it had complied with the ACM's order, but the regulator said the company had failed to do so "on several points" after analysing Apple's statement.
"The most important one is that Apple has failed to adjust its conditions, as a result of which dating app providers are still unable to use other payment systems. At the moment, dating-app providers can merely express their ‘interest’," the ACM wrote.
"In addition, Apple has raised several barriers for dating-app providers to the use of third-party payment systems.
"For example, Apple seemingly forces app providers to make a choice: Either refer to payment systems outside of the app or to an alternative payment system. That is not allowed. Providers must be able to choose both options."
Apple has faced ongoing criticism for its insistence apps available via its app store must use its payment system, which attracts a fee of up to 30 percent, depending on how popular the app is.
This is one of the reasons for the protracted legal fight between the company and Epic Games, the creator of popular battle royale game Fortnite.
Meanwhile, there could be more trouble for the iPhone maker in the Netherlands and elsewhere after its long-running legal dispute with Ericsson took another twist.
The Swedish telecoms company has filed injunctions in the Netherlands, Germany, Belgium and Brazil, claiming Apple is infringing on its mobile communications patents.
While the company hasn't yet asked for bans on importing iPhones into those companies this time, it has done so in the past when those same patents were infringed.
Apple has previously licensed Ericsson's patents, but didn't renew them when they expired. Website 9to5Mac speculated this was likely to try and negotiate a smaller fee.
Florian Mueller, a patent litigation expert, said he was surprised Ericsson hasn't yet filed suit in the UK, because it has become a "very attractive jurisdiction".
"Still, my bets would be on the UK for the next European jurisdiction in which Ericsson might file, depending on how Apple responds to this week's developments," he wrote.
Apple has countersued Ericsson for infringing three of its patents, related to wireless charging and antennas.