Remove "Software Update" app from device
If your mobile is rooted, use System App Remove tool from play store &amp; remove the system App.

If mobile is Non-rooted : I don't think that voonik advertise is generated from your software update as it is a pre installed system app, but still you can try to clear cache &amp; force stop and check if advertise is still popping up or not. If it is still popping then check other apps you have downloaded...  

Last option should be factory reset..