A: Are you getting multiple codes you did not request for Google Account recovery/password resets?

Question

READ ALL of this before posting:  Please ONLY use the blue "Reply" option:

A)  What:
Since the start of September users have been reporting receiving multiple verification codes from Google that they did not request, as though someone is trying to access the users's Google Accounts.
Other users are getting messages telling them that "their" Google Account passwords have been changed or even that "their" Google Accounts have been deleted.
Note that Google is aware of the issue and I will update here when I hear anything. 
B)  Why:
Some third party companies appear to have suffered data leaks which have resulted in (primarily) mobile phone number lists being leaked to the troublemakers.  These troublemakers are probably doing this to make money from the sending of the codes/messages, nothing more.  Meaning-  they are not trying to get access to your (unknown to them) Google Accounts.
Note that this is not something which you or Google can stop, since your number is already leaked and "out there".
In the case of this being Google Account recovery codes-  please be reassured by the fact that you are getting the recovery codes sent to you, which means that the troublemaker is not getting them.
C)  What you should do:
Review your security carefully, running a security check-up here:  https://myaccount.google.com/security-checkup (and enable two-step verification!) and make sure that you have active virus detection/removal software.  
D)  Posting a reply:
Share only the short answers to five questions in that specific order, and using "Reply" (do not use "Add a comment"):
What are you getting?  Recovery codes?  Or notifications of password changes or Google Account deletions?
What country are you in?
What language is the message in?
Who is your mobile provider?
Anything else is off topic and will be treated as such, thanks for understanding.
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Please use this option if you are going to post a reply:

The Lady from UNCLE · Accepted Answer

a)  Thank you so much to everyone contributing their info on this issue addressed by this thread.  Thank you also for bearing with me on the formatting of your reply and using "Reply" and not "Add a Comment".  It makes a huge difference to Google and I.
b)  In review:
It appears that Australian users have not seen activity in this regard since the end of September.
The activity has shifted to the UK (with one exception-  one user is in Iceland). 
The new activity seems to be more spread out across the main UK mobile networks (and is always in English).
The activity appears to have nothing to do with users's Google Accounts, but is more about using their leaked phone numbers to make money from.  Nasty.

c)  Current Advice:  Since this is still not impacting on users's Google Accounts and it is not something which can be fixed by users's mobile phone networks or by Google, it is still best to-
do a security check-up (see Step 1 here:  https://support.google.com/accounts/answer/46526),
install and use good anti-virus software, and-
seriously consider two-step verification (also under Step 1 in the link above).
I advocate two-step verification for Google Accounts (check out Passkey!), because if Google do tighten security again in response, many users could find themselves locked out of their Google Accounts if Google find it necessary to ramp up security in future.
d)  Final Note:  I am going to close this thread for the time being, having passed on everyone's generously shared data to Google, but assure you that I will still be monitoring the situation and may reopen the thread to allow more data to be shared.