Why do controlled medications like Elvanse sometimes require a paper prescription instead of an e-prescription?

This is part of the Misuse of Drugs Regulations 2001. UK law places Lisdexamfetamine and Methylphenidate as a Schedule 2 controlled drugs. There is an argument that this law is in need of update, but we must follow it regardless. While NHS prescriptions for Controlled drugs can be electroinic, Private prescriptions must remain paper-based and The prescription must meet strict legal requirements with specific rules about the wording, quantity, dose instructions, and prescriber's authorisation. For patients, this can sometimes mean waiting a little longer for the prescription to arrive at the pharmacy, particularly if it needs to be printed, signed (where required), and sent securely. Please rest assured however that the delay frustrates us too! Its why when we set reminders for your prescription we set them a week before its due to give us time to get everything done