Universal Credit Managed Payments

Universal Credit

Hi
My tenant has outstayed her 2 months notice period and is nearly 6 months in arrears but she's refusing to communicate with me to discuss her situation despite my letters and emails. I suspect she is getting Universal Credit so I looked into applying for managed payments, but it seems as a private landlord I have no right to know if she's claiming anything or not. To apply for managed payments I need to know the tenant's date of birth but my so called 'agent' wont give me that information or apply on my behalf. Can anyone tell me how I can legitimately find out my tenant's date of birth so I can at least apply to see if she's claiming benefits? I feel completely powerless.