Mine is the same. She’s a little over 7 weeks old and really only smiles when waking up from a nap or having gas. I can’t wait until she smiles for real and starts laughing!
Mines been smiling since birth he's now 6 weeks old but my friends 6 month old barely smiled till 5 months. They all progress on their own timeline so don't worry
Totally normal and every baby is different... my girl will laugh in her sleep or smile sometimes when she's dozing and i kiss her but otherwise not really smiling yet