Your ammonite probably is...

Gonioclymenia

Gonioclymenia had a grooved venter and wide umbilicus, along with very faint radial ribs. Its suture was goniatitc. It was from the Upper Devonian.

Image by Ghedoghedo, CC BY-SA 4., https://commons.wikimedia.org/wiki/File:Gonioclymenia_sp_dev_marocco.JPG