Typically the reason for this error is that your link does not correspond to the service you would like to order. For example, when ordering subscribers, you inserted a link to the video, but not to the channel. Or you selected the wrong social network on the widget.
Please check all requirements in the service description. If you would like to increase YouTube views , your video should be unrestricted and public. In case these requirements are not met, your link could be marked as “invalid”.
If your particular case doesn't fit any description above, please contact us via live-chat.