Can you help my sister and her NINO number ?

[WingsofaAngel]

My sister is employed at her local nursery run by other people where she lives.

They seem to be using a temporary National Insurance Number.

She did supply them with all the correct details.

Who does she contact to get it changed.
Nobody seems to know and pass her on.
TIA

Is it LA or private? I think these days they're not even allowed to use temporary numbers!

Who processes the wages? The payroll clerk will change it on the payroll system.

It's private. She has found out that the accountant should be the one sorting it out.
I think they need to use on who knows what he/she is doing.