YOU SAID:

It seems like I could've done this before.

INTO JAPANESE

この前にやんだことができるようです。

BACK INTO ENGLISH

Seems to have stopped this ago;

INTO JAPANESE

この前止まったようで

BACK INTO ENGLISH

That stopped this before

INTO JAPANESE

それは前にこれを停止

BACK INTO ENGLISH

It stopped this before

INTO JAPANESE

それは前にこれを停止してください。

BACK INTO ENGLISH

Please stop it before that.

INTO JAPANESE

それ以前にやめてください。

BACK INTO ENGLISH

Please stop it before that.