Downloading from shop is very slow

Hi,

for at least a week all the apps I try to download from Windows Shop are downloading really slow. It doesn't matter if I use wi-fi or cellural data, also it doesn't matter if I update an app or download a new one. Sometimes it can take half a day and I don't know the cause. All other apps work good - readit, tubecast etc. The problem is with shop only. What can I do about this?