I have this shape imported from an svg file.

But I'm not able to make that sharp edge smooth. When I use Bevel, I get weird behaviour from the final vertex:

Clamp overlap solves the issue but doen't allow me to control the weight of the bevel.
I've tried subdividing, scaling, adding inset faces and subdiving surface but everytime I get extra faces from this vertes:

Sorry, I can't add the .blend file but I'm not allowed to.
I can assure you that I've tried any answer related to this I've found here in this Q&A site but nothing helped. I know it's a beginner question but any help would be very appreciated.

