Having trouble to upload a snap picture at Dtube

This is the fifth time i tried uploading a video on Dtube.
The video successfully uploads, but the snap picture upload does not seem to upload for any reason.

Because of this issue, it does not allow me to upload my video.
I have also tried switching to different browser and also considered changing the snap picture to different sizes.

Any one facing the same issue?

@Dtube please help me out.