Issuing a Section 21 on the grounds of tenant anti social behaviour

Possession - Section 8 and Section 21

I wonder if you can help.

My question relates to whether I can issue a Section 21 to a tenant who is causing anti social behaviour in an apartment building we manage.

The back story is that a landlord client of mine bought a development of apartments in January of this year. All tenants in the apartments (of which there are 24 of) had previously been issued AST's on their move in by the previous agent. On takeover of the management at the end of January this year I wrote to all tenants advising them of the buyout, who their new landlord is, that we would be managing their building, that we carry out maintenance for them, and that all other terms of their AST's in general would not be changing. I did not issue new AST's to the tenants in the apartments (of which there are 24 of) but since Feb 1st all tenants have been paying their rents to us.

The tenant who is causing the anti social behaviour in the development is now outside the initial fixed term of her AST (her tenancy is now running periodic), and although the Housing Benefit have paid her rent up to date she is causing so many problems with the other residents in the building that I need her out.

I believe that dispite the fact a new AST was not issued to the tenant in question on the landlords buyout, because we wrote to her, because we have received the rent from her (Housing Benefit), and because we have spoken / emailed with her on many occasions since we have a continuing legal contract. My question therefore is can I issue a Section 21 on this basis and would this 'ongoing enduring contract' stand up in tenancy law ?

I'm living in hope of hearing from you soon !

Best Regards,
Nigel Loughtman
Tiger Property Partners Ltd