Receiving Microsoft verification codes for unknown app names — what exactly triggers these SMS?

I’ve received Microsoft SMS messages saying:

“Use verification code [code] for My Total Comp UAT authentication.”

and later:

“Use verification code [code] for clclouddev001 authentication.”
I did not initiate either request and I don’t recognize these application names.

I’m trying to understand the technical side:

• Are My Total Comp UAT and clclouddev001 likely application/display names from Microsoft Entra/Azure authentication?
• Does receiving this SMS mean someone manually entered my phone number into that application?
• Could this happen because my number is already stored somewhere in an account or test environment?
• Is there any way for me, as the recipient of the SMS, to identify which application/tenant generated the request?

I’m not asking whether my Microsoft account was hacked — I mainly want to understand what process causes Microsoft to send an SMS in this exact format.