Since 2018, UK cannabis law has changed under the Misuse of Drugs Regulations...

https://www.tntmagazine.com/leisure-entertainment/leisure/why-is-cannabis-still-illegal-in-the-uk-the-history-behind-medical-cannabis-law/

Since 2018, UK cannabis law has changed under the Misuse of Drugs Regulations 2001, not the Misuse of Drugs Act 1971. Specialist doctors can now prescribe some cannabis-based medicines, like Sativex and Epidyolex, which are licensed for medical use