Here may be various causes, but the most likely is that the _default option is not checked in the display settings. "
Indeed, since PrestaShop 1.5, the name of the files of the images is often extended by a dash and the name of the theme as suffix. Thus the file 4562_smal.jpg is renamed 4562_small_default.jpg for the default theme of PrestaShop.
In this case, it must be indicated to PrestaPricing so that it looks for and finds the right files, by checking this option:
What should I do if product photos are not displayed in PrestaPricing and PrestaCategory?
Alternatively, your theme requires replacing the word _default with the name of your theme in the same place.
For example, if your theme is named my_theme, depending on the settings in PrestaShop, you may need to set PrestaPricing like this (do not forget the hyphen):
Finally, it may be necessary to empty the PrestaPricing cache, for all images, by clicking on this button representing a barred watch in the right part of the "Pictures" sub tab of the "Variations and images" tab:
All that remains is to refresh the display of the tables.
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