WD Backup - Failed to create backup plan

trying to set up the wd backup, configure new backup job, select my dropbox (signed in) review back up settings, click start backup and get error message “failed to create backup plan”
i can use the WD access and upload files manually to the EX2 Ultra but not to create a backup job. I have reinstalled the software, i have the dropbox cloud app configured

Hi kfg007,

WD Backup is recommended to data backs up on DAS devices. You should go with My Cloud Dropbox App to backup your Dropbox data on My Cloud EX2 Ultra. Here, My Cloud Dropbox App is a file-hosting service which syncs content between a multi-bay My Cloud drive and a users Dropbox account.

https://support.wdc.com/knowledgebase/answer.aspx?ID=10474#dropbox5