When original Image is smaller than the required template sizes

You have an original image with dimensions 700px × 700px and you are about to create published images of the following size: 1080px x 1920px.  

STEP-BY-STEP 

1. 1. Configure the Resize Command
   2. Provide width and height as 1080 × 1920
   3. Enable Proportional Scaling by clicking Proportional checkbox YES.
   4. Enable Overflow by clicking Overflow checkbox YES
   5. Scale up = NO

The proportional resize image will be: 700px ×  700px

HOW TO SCALE UP? 

If you instead choose Scale up = Yes

The resize image will be: 1920 × 1920

That is closer to your wanted format 1080 × 1920

The last step you need to do is to enable crop. 

ENABLE CROP COMMAND TO YOUR IMAGE TEMPLATE 

• Open up your image template and scroll down to Add Commend
• Choose and add Crop Crop Command

• Provide the width and height as 1080 × 1920
• Choose the Gravity (as center). The cropping will start from the center of the image
• (Choose ‘YES’ for ‘Use Crop Point’ if you want to override the cropping by manually choosing the Focus Point)

The cropped image will be: 1080px × 1920px with the content cropped