That's just "Smart" or "Smart Automobile" AFAIK, unless you're referring to some other brand I'm unaware of. That brand was established in 2019. Smartcar Inc., from OP, has been around since 2015.
The Mercedes "Smart" car has been around since the late 90's.
Oh ok. Not "Smartcar" though. "Smartcar" != "Smart" or "Smart Fortwo". So unless the claim is that any name with "smart" in it is infringing on Mercedes...