Hey there, and welcome to Apple Support Communities Azitahamburg,
From our understanding, your iPhone storage is full even after purchasing more iCloud space. We can certainly understand your concern and can help provide some insight.
Please keep in mind, purchasing more iCloud storage will not change the devices physical storage capacity. In order to do this you will have to manually delete any unwanted files to make space. Check out this link for more information on how to manage your storage: Manage your photo and video storage - Apple Support
Let us know if that helps and kindest regards!