'のために’ Usage - Why is 「私の ため に 日本語 で 話してください」 incorrect?

Question

For reference, I don't have a teacher.

An online resource I used described 'のために' as being 'for the benefit' of when a verb is involved - the structure being NOUN のために VERB

The example given was

日本語 が わからない人 の ため に えいご で 話してください
Please speak English for the benefit of people that don't understand Japanese.

The sentence I was trying to write was: Please speak Japanese for the benefit of me / Please speak JAPANESE for MY benefit. What I got was:

私の ため に 日本語 で 話してください

My Japanese friends don't understand what I'm trying to say at all and can't point out what's wrong with this sentence - just that it's gibberish.

'I' is technically a noun. 'To speak' is the verb. Where did I go wrong?

Answer 1

I think 私のために、日本語で話してください is grammatically correct. However if you are non-Japanese, your Japanese friends might be a bit confused because they would expect to be said "私のために、英語で話してください" so that you could understand.

If you said 私の日本語の勉強のために、日本語で話してください, they would be able to understand what you said.

Answer 2

This might be a mistake in your post rather than what you actually wrote to your Japanese friends, however what you've written in Japanese is:

Please speak Japanese for my benefit

Not

Please speak English for my benefit

If this is actually what you wrote, this would explain their confusion. Your sentence is fine, there are slightly more natural ways to express the same thing, but there should be no reason for any confusion beyond you saying Japanese instead of English.