In 2018, the UK updated the Misuse of Drugs Regulations 2001—not the 1971...

https://penelopesimpressivejournal.urbanvellum.com/posts/why-do-evidence-based-recommendations-not-always-become-policy-in-uk-drug-law

In 2018, the UK updated the Misuse of Drugs Regulations 2001—not the 1971 Act—to allow specialist doctors to prescribe cannabis-based medicines like Sativex and Epidyolex. Despite this, cannabis remains a Class B drug for recreational use