Hello @Mfirwana,
Sorry for this inconvenience.
Make sure that WPDM and all add-ons you are using of WPDM are in the latest version. Current version of WPDM free is 3.2.34 and WPDM Directory addon is 4.4.1. If you can’t update it directry from WordPress dashboard, Please update from here.
If, still the problem exists then please share your admin login credentials with us in a private reply so that we can debug and give you a better solution about it?
Best Regards