Magento 2 product image gallery not responsive and resizing on mobile side

[Magentobiz_com]

When I upgraded to 2.2.6, My product image gallery is not responsive and resizing on mobile side, and it works well on PC.  

[Manthan Dave]

Hi @Magentobiz_com

Looking at the screenshot i think you are using readymade / custom theme for your project.

To check the responsive on mobile - kindly switch your theme to Magento 2 's default Luma theme and then check 

Because looking at the Magento 2.2.6 Vanila version with Luma theme its showing correctly 

so you might have issue with your theme !

Hope it helps !