If the connection between the Cloud and the printer is disrupted mid-print, this can cause the failed print job to get stuck as In progress. This means that any future print jobs sent to your printer will end up in the queue and won't start to print.
If this happens, you need to login to your account on cloud.smart3d.tech, click on Printers and cancel the job In progress:
You should be able to click Print on any of the pending print jobs in the queue or send new jobs straight away.