IVLTaxAccount

I registered a company in September 2022, I am the sole director. I am not taking wages or getting paid any sort of income from the business. I am employed by another company for which I am a PAYE. All my tax is taken at source from my employer. Do I need to register for self return? I tried and it asked me to enter my Unique Reference Number, something I've never been provided before. Everywhere I look it says that I get one after I sign up for self return, but during signup it asks for it. Maybe I'm missing something so would be grateful for any advice on this. I did notice that when I tried to sign up, there was a tick box. On the box it said, if you are a director of a company and get taxed at source via PAYE you don't need to do a self assessment. This is be the case one day, but as of current I'm reinvesting all of the profit back into the business.