Which is why

[Talab1234]

Joe was instructed to send the payments to Bob which is why there was no need to send it to Bob again.

Is this sentence grammatically correct?

 

[Barque]

It is, but it doesn't make much sense to me.

 

[jutfrank]

Is this sentence grammatically correct?

Please stop asking us this. It's not the right question.

 

[Barque]

Please stop asking us this. It's not the right question.

Talab, I assure you that any ungrammatical sentences you come up with will always be corrected, even if you don't ask about the grammar. That's the first thing we notice.

Ask if a sentence is appropriate. Not if it's grammatical.

For example, "The man burns in the Norwegian philosophy of the mud" is a perfectly grammatical sentence. It's also a completely senseless sentence.

Do you get the difference?

I think you assume that the sentences you make up make sense always and you just need to check the grammar. It isn't so simple.