To add serial number/IMEI for a product with variant on mobile please follow the below steps:
Step 1: Click on Products in your swipe application.
Step 2: Click on + New Product to add a new product.
Step 3: Fill in the required details of product and click on Add Product.
Example. Here we are creating Oppo phone as a product.
Step 4: After creating the product, view product and click on the three dots.
Step 5: Click on Add Variant to add multiple variants of the selected product.
Step 6: Fill in the variant details required, also enable the Manage Inventory Using Serial Number toggle to make variant with serial numbers.
Next click on Add Variant.
Example. Here we are creating variant as Oppo slim phone
Step 7: Add serial number to the variant by clicking on Add new Serial Number.
Step 8: Type in the desired serial number and then click on Add Serial Number.