Forum - C4Dzone

Hi everyone.
I received an obj from a friend but this has a problem:
all the faces seem to be separate, so when I insert a subdivision surface I have a problem (as you can see in the attached images).
Does anyone know a solution for this?

Go in edge mode and use the dissolve tool in order to create all quadrangle, the triangles must be avoided, after that use the optimize tool

Thank you so much. I had also arrived at this solution, trying everything.
Thanks again.

but instead of "dissolve" I use "melt" seems to work better .. I do not know why