How do I report speech containing "must not"?

What's the form for reporting speech that contains must not?

I mean:

I can't come to the meeting on Monday => She told me she couldn't come to the meeting on Monday.

You must talk to me => She said you had to talk to me.

Till now, there's no problem, but what should I use with must not?

I think that I can't do the following:

You must not talk to me => She said that you didn't have to talk to me.

because

Must not <> Have to

Am I right?

Solution 1:

The negative form of must is mustn't. So you can say this:

You must not talk to me. => She said you mustn't talk to me.

The past form of must is also must, so you don't need to change the form of the verb when reporting speech in this manner.

However, the form mustn't is rarely used in American English, though I believe that it's commoner in the UK. Instead, most Americans would substitute shouldn't:

You must not talk to me. => She said you shouldn't talk to me.

Solution 2:

How about, "She said you were not to talk to me"?

Solution 3:

I don't know if it is 'good' English, but it is common from where I grew up in the north of England.

She said you had not to talk to me