Back pay voluntary self employed class 2 NI

I am a landlord and rental income is my primary income, I started in spetember 2017, september 2017 to september 2019 this was with lodgers and I used the rent a room allowance, after this it without the allowance. I thought I was paying voluntary class 2 NI payments each year, but the online portal only shows one Full year, is it posible to to back pay theese years? at what rate would I pay and how?

Hi,

In some cases, an individual who rents our property can pay Class 2 NICs. However it would appear from your enquiry that this income is derived from renting out a room in your own home?  If this is the case, this would not entitle you to pay Class 2 NICs

You can see guidance here:

NIM74250 - Class 2 National Insurance contributions: special cases: property and investment income

Thank you.