Try Name That Plant forum, and be sure to state what zone and where in the world you live.

No it has never had leaves. Not for my friend or me. - but you helped me identify something I find in my yard sometimes :), Thanks you for the response!

Ruellia. Possibly Ruellia humilis. https://www.morningskygreenery.com/product/ruellia-humilis/

We put plastic over our ground cover to try and kill it and then mulch on top. Don't want to use pesticides because we want to replant in the garden.... Well the ground cover survived and grew through the plastic. It will not die. I rip it alk out every year and it comes back no matter what. It's a fight that never ends. It chokes out my other plants. This year I'm planning on launching a full attack.