You can only upload up to 100 variants per product. If you have a product with more than 100 variants then you can either delete some or split the products into 2 (or more).
To remove a variant, simply deselect it by unticking the checkbox:
To split the products, you need to upload the product twice in your Shopify store. Let’s say a product has 200 variants. You can split the products into 2 with 100 variants each.
Upload the product with the first 100 variants.
Navigate back to the search page then click the green checkmark button.
Click the ‘+’ button to import the product again.
Upload the product and select 101-200 variants.
You can now see 2 products in your Shopify store with all of the variants.
Short URL to this FAQ: https://www.salehoo.com/u/apj7j