YOU SAID:

stop my mom is on the phone

INTO JAPANESE

私のお母さんが電話に出ているのをやめる

BACK INTO ENGLISH

Stop my mom being on the phone

INTO JAPANESE

私の母が電話に出ているのをやめる

BACK INTO ENGLISH

Stop my mother being on the phone

INTO JAPANESE

私の母が電話に出ないようにする

BACK INTO ENGLISH

I will prevent my mother from answering the phone

INTO JAPANESE

母が電話に出られないようにする

BACK INTO ENGLISH

I will prevent my mother from answering the phone