Error attaching image but uploaded successfully to "public/files/" folder but raises ValidationError Folder Mandatory

here is my browser console

Traceback (most recent call last):
File “/home/frappe/frappe-bench/apps/frappe/frappe/handler.py”, line 109, in uploadfile
ret = frappe.utils.file_manager.upload()
File “/home/frappe/frappe-bench/apps/frappe/frappe/utils/file_manager.py”, line 35, in upload
file_doc = get_file_doc()
File “/home/frappe/frappe-bench/apps/frappe/frappe/utils/file_manager.py”, line 68, in get_file_doc
file_doc = save_url(r.file_url, r.filename, dt, dn, folder, is_private)
File “/home/frappe/frappe-bench/apps/frappe/frappe/utils/file_manager.py”, line 97, in save_url
f.insert();
File “/home/frappe/frappe-bench/apps/frappe/frappe/model/document.py”, line 218, in insert
self.run_before_save_methods()
File “/home/frappe/frappe-bench/apps/frappe/frappe/model/document.py”, line 808, in run_before_save_methods
self.run_method(“validate”)
File “/home/frappe/frappe-bench/apps/frappe/frappe/model/document.py”, line 702, in run_method
out = Document.hook(fn)(self, *args, **kwargs)
File “/home/frappe/frappe-bench/apps/frappe/frappe/model/document.py”, line 965, in composer
return composed(self, method, *args, **kwargs)
File “/home/frappe/frappe-bench/apps/frappe/frappe/model/document.py”, line 948, in runner
add_to_return_value(self, fn(self, *args, **kwargs))
File “/home/frappe/frappe-bench/apps/frappe/frappe/model/document.py”, line 696, in
fn = lambda self, *args, **kwargs: getattr(self, method)(*args, **kwargs)
File “/home/frappe/frappe-bench/apps/frappe/frappe/core/doctype/file/file.py”, line 69, in validate
self.validate_folder()
File “/home/frappe/frappe-bench/apps/frappe/frappe/core/doctype/file/file.py”, line 131, in validate_folder
frappe.throw(_(“Folder is mandatory”))
File “/home/frappe/frappe-bench/apps/frappe/frappe/init.py”, line 319, in throw
msgprint(msg, raise_exception=exc, title=title, indicator=‘red’)
File “/home/frappe/frappe-bench/apps/frappe/frappe/init.py”, line 309, in msgprint
_raise_exception()
File “/home/frappe/frappe-bench/apps/frappe/frappe/init.py”, line 282, in _raise_exception
raise raise_exception(encode(msg))
ValidationError: Folder is mandatory