YOU SAID:

It's not my fault but

INTO JAPANESE

私のせいではないが、

BACK INTO ENGLISH

Is not my fault

INTO JAPANESE

私のせいではないです。

BACK INTO ENGLISH

It is not my fault.

INTO JAPANESE

私のせいじゃないよ。

BACK INTO ENGLISH

It's not my fault.

INTO JAPANESE

私のせいじゃないよ。

BACK INTO ENGLISH

It's not my fault.