Hi JinQin W,
Please contact the HMRC helpline on 0300 200 3310 as we will require to access your records to determine the correct UTR.
You should only have one UTR.
We will also be able to update your address when you call.
You can also contact us online via our Webchat Service Self Assessment: general enquiries - GOV.UK (www.gov.uk) by clicking on “Ask HMRC online.
Self Assessment: general enquiries