Maybe they have changed things. The UK has some peculiar rules when it comes to importing where if the consignment is under £135 the seller needs to pay any taxes due directly with HMRC (His Majesty’s Revenue and Customs) - for anything above that, then the buyer pays any taxes due to the courier company in order to release the goods.
Before the UK left the European Union, this wasn’t necessary for counties within the EU (UK, Italy). It was a customs union and goods could transit freely with the EU - so ordering something from Germany was no different from ordering something from the UK. This has since changed, and a lot of EU countries cannot be bothered to deal with the extra bureaucracy and simply can’t be bothered with the UK anymore (I had personal experience with this when trying to order a watch strap from Germany). It will take a while to adjust, and maybe some companies are adjusting themselves if the UK is a significant market for them.
🤷♂️