The PDQ Deploy server used by the deployment has a filter which is preventing the deployment from going to this target.
There is either an Exclusions or Inclusions filter which is preventing the target(s) from receiving the deployment.
The filter must be changed to allow the deployment to continue. To modify your defined filters go to the Target Filters panel under Preferences. (note the two different tabs: Exclusions and Inclusions). In the example below, any computer named "homer" or any computer that has a name which begins with mail-v or svr-dc would be excluded from deployments.