Has the valve of your inflatable SUP become unseated? The force of air that leaves an inflatable SUP board when you deflate it may pop the valve out. If this happens, it may need to be re-seated and tightened. A wrench/tool came with your board. Please unscrew and remove the nozzle, then put it back on and tighten it with the plastic tool. Be careful with the threads as they are like a regular screw. Please be careful to avoid cross threading. It will screw on easily.
Here is a quick video on how to fix it:
We hope you liked it!