Not requested verification code SMS

Last night I updated the latest release of the microG Service core. My intention was to fix the intense growing database problem with CWA. This worked out pretty well. Another issue I was hoping to get some progress was finally be able to register to the TIER App (eScooter rental service). Even this was now possible because basic firebase auth are now implemented in the latest release in the service core. Thanks for this great update!
About 30min after I received my TIER verification sms something unexpected happened. I also received an sms by Lidl (German international discount supermarket chain) with another verification code. I never requested this code or even have the Lidl App installed. In general it is the first time a received a verification sms without request.
This might all be a temporal coincident but I just want to check if anybody else experienced something similar like this here?

I also emailed TIER if this is a common issue.

The report references the microG Service core release and its Firebase authentication support, but names no source file, test, or entry point. Start by reviewing the authentication SMS flow and the timing of the TIER and Lidl messages. Done would require determining whether GmsCore caused the unsolicited SMS and documenting reproducible evidence; the issue currently provides no code-level acceptance criteria.