Disrespectful 12 year old

[missbrowneyes]

Hi all. I am new here so please go gentle! I have a 12 year old daughter whose behaviour is absolutely vile. Speaks to me like absolute crap, no kind of discipline ever works with her from me or my husband. I have 2 other children and the younger one is re creating her behaviour.
I am literally at my wits end with her and cannot bare to be around her at the moment. She has always been bad but is literally uncontrollable

Any change? Do you manage any one to one time away from the house to just be with her. Do something grown up with her,go to a cafe maybe?

Be very strict - remove all privileges like phone / screen time/ laptops etc until her behaviour changes.
Be tough now so this doesn't escalate.

Tell her you need her to model brilliant behaviour for her siblings etc ... yes have some 1-2-1 time together.