keep telling / been telling / telling

Question

If a person or thing( e.g. voicemail) keeps repeating something, or telling me the same thing for a specific time period (e.g. an argument, discussion etc.), which one of the above do I have to use?

For example:

Person A:

I'll take out the trash after dinner!

Person B:

That is what you are telling me for the last 3 days.

That is what you have been telling me for the last 3 days.

That is what you keep telling me for the last 3 days.

or

Voicemail :

We will be with you shortly.

You(what you're thinking):

That's what it keeps telling me for 20 min now.

That's what it has been telling me for 20 min now.

That's what it is telling me for 20 min now.

Answer 1

In both your examples, the present continuous versions ("That is what you are telling me for the last 3 days") are definitely incorrect -- because the sentence also has a time reference to a time interval that started in the past and extends until right now, in English it requires present perfect continuous "That is what you have been telling me for the last 3 days", not present continuous. The versions with "keep" sound fine too.

Answer 2

In the examples given, only the present perfect continuous form is correct. That is, with the ongoing temporal specification, the correct form is:

Subject + has/have been + verb+ing + ongoing temporal specification
I have been waiting since 8 o'clock.
I have been waiting for 20 minutes.
She has been there since this morning.

Thus:

That is what you have been telling me for the last 3 days.

or

That's what it has been telling me for 20 min now.

The other versions are not correct:

That is what you are telling me for the last 3 days.
That is what you keep telling me for the last 3 days.

However, they do work without the temporal clause:

That is what you are telling me.
That is what you keep telling me.