product pictures will be present in very large size

Since some days I have the problem, that the productpictures will be present in only large size. I have already tried Force Regenerate Thumbnails but the productpictures are still big.
I use WordPress 4.9.8 withTheme Dazzling and Woocommerce Version 3.4.4.
my shopurl is:
Hope somebody can help me there.
kindly regards

Hi there

Thank you for the question,
im not sure if this problem is theme related, have you tried to change settings in the appearance > customize and woocommerce part that changes image sizes? (regenerate thumbnails must be run after these settings were changed)
to make sure this is a theme problem please activate one of default wordpress theme and check if you have the same problem, let me know results