Not receiving single-use codes when two-step verification is turned on

Hello!

I'm not receiving single-use codes on my mobile phone when Two-step verification is turned on. As soon as I turn TSV off, the single-use codes reach me within a minute I request it. But with TSV on, they never arrive. Due to this, I have to keep TSV turned off.

My previous post regarding this was locked, telling me there is a new Microsoft account secure online form I can use, but I'd like to inform that I have already tried that form a month ago itself. They only told me that my issue is under investigation and they will get in touch with me, but they still closed my support request without providing me a solution.

It has been 16 days now, I haven't heard from them regarding this issue. I'm being taken for granted and my issue is classified as "General Issue", while this is posing me a big security threat, as I have to keep TSV turned off during this time in order to be able to use single-use codes. Now I don't know if/when anyone else has stolen my password and logs in to my account using that. Outlook.com, unlike other email services, doesn't even informs us if our session is open somewhere else, neither it gives an option to log out remotely from all other sessions, or even an access history log.

All I want is to keep TSV turned on so that my account stays secure, without losing the ability to use single-use codes.

Can you at least tell me whether it is really a bug or Microsoft intentionally designed the system this way that we don't receive single-use code when TSV is turned on?

Also, if this is a bug and single-use codes start to work with TSV turned on, in that case, will I again receive a second OTP code on my phone for TSV, after logging in with a single-use code, which I also receive on my phone, hence the purpose of TSV (i.e. something you know and something you have) is already fulfilled by the single-use code.

Thanks!