Ccarlisle29

Hi, I have recently moved home, and when trying to update my address for HMRC, I had to create a new sign-in for Government Gateway as mine had been deactivated for inactivity, When trying to use my NI number is was saying it did not match my details, like name, DOB, etc. I spoke with an online chat and had my NI number posted to me, which is the same Letters and numbers but in a different order to what I originally thought, I have sent my last 5 years P60s to yourselves and am awaiting a response on what I should do next? Will my NI numbers be combined? Do I need to pay more? Have I overpaid? I really need an answer so I can stop panicking! My 2018-2019 P60s are the correct number, Anything from 19-24 has been the wrong number, What do I need to do next? Please help,