Is this sentence correct?

Mister MicawberMom has said that I am not allowed to talk to strangers any time I am alone.

Why the fragment with the preapoesition "at any time I am alone" is considered to be incorrect?

It is not a native construction; it is stilted.

Thank you kindly for your help.

Sorry to double post, but why "Mom's said" cannot be left as a contradiction of "has said"?

It is uncommon enough to be confusing, and it is slightly incorrect, since a contraction of 'has' with a noun is pronounced [?z], not [z], as it is with pronouns (e.g., he's [hi:z]).

So is it considered as a grammatical mistake, or is it acceptable in terms of grammar. I am asking because I encountered a lot of those forms on the Internet, used presumably by native speakers.

First, punctuation is not a part of grammar. Contractions are not words; they are transcriptions of the spoken language, and as such you may use whatever you like but it should be clear and intelligible. I have told that 'Mon's' for 'Mom has' is not.

Second, you may use the internet for native utterances (if you are sure the writer is native), but you cannot use it for generally accepted

OK thanks again. I also have yet another question in terms of proper grammar. Referring to the form of the sentence - it is reported speech. So treating "Mum's said" as an introductory verb "has said" it cannot be contracted, is that right? Is there a general rule for introductory verbs in reported speech stating that they cannot be contracted. I mean that I cannot write: She's say, she'll

AnonymousOK thanks again. I also have yet another question in terms of proper grammar. Referring to the form of the sentence - it is reported speech. So treating "Mum's said" as an introductory verb "has said" it cannot be contracted, is that right? Is there a general rule for introductory verbs in reported speech stating that they cannot be contracted. I mean that I cann