The method of notification is as agreed in your Contract of employment subject to the rules of self-certification, which you probably signed when you first joined your employment. The usual requirements are:
Notify your employer on the first day of sickness before 10am.
Up to 7 days on self-certification.
Over 7 days note from your GP.
But I note your employer wishes to be notified on a daily basis, which is unusual, and if not in your contract, ask why. Your employer may pay you, which will also be in your contract you will then be on statutory sick pay for up to 28 weeks, which is paid by your employer.
If you find it difficult to notify your employer each day, explain this to them and request that you may be excused.