Spouse Visa and child benefit???

Hi,
My husband is on spouse visa along with his two dependant children from his previous marriage. Now i have given a birth last year to my baby who is a British born. I wanted to claim child tax credit and child benefit for my bilogical son only as other 2 kids are not my bilogical and also not born in UK. There biometric card also state no public funds. But when i contacted HMRC. When i gave all my information. They said you already have 2 under 16 living at your household so this way you are not entitled to claim for the third one straight by skiping first 2 children. We can give you for first 2 kids. This is the law. I explained my husband and kids status, that how can i claim on behalf of them who are subject to immigration control. HMRC explained as i am British and kids are living with me in a same household so i am responsible for them because i am married to their father. They started Child Tax Credit for my step children and i am claiming child benefit for my bilogical baby. I was scared to claim for them. But HMRC asked me that y am i not claiming CHB for them as i am e titled to get. Now i am bit worried and asking different lawyers that am i getting wrong child tax credit? Every lawyer is saying that u are their british step mother and they are giving it to you not to children.
Please someone help me and guide me.
Thanks alot
Bina

I wanted to claim child tax credit and child benefit for my bilogical son only as other 2 kids are not my bilogical and also not born in UK. There biometric card also state no public funds.

You can claim for all children. It is YOU that claims NOT the children.

Child Benefit MUST be in your name only.

Child Tax Credits MUST be in JOINT names with your spouse and you must not claim as a single person.