amka

I've been doing paper returns for around 20 years. I have a day job where I pay PAYE and I'm a landlord, for which I do a self assessment. I'm not too clued up on online matters but think it's time to go online. I've already got a UTR but when I watched online videos, they say - customers will be sent a UTR by post. I can't understand this. If I've already got one, why would I need a new one? Hope someone can clarify.