Modify option when to add new items is not coming up - any suggestions?

[SarahMarsh]

Hey there

I am trying to bulk upload new items to Square using the instructions online:

1. Visit Items in your online Square Dashboard.

2. Click Actions > Import Library.

3. Select Modify Item Library to add new items and update existing items, or Replace Item Library to delete all existing items and replace them with your uploaded items.

There is no option for me to 'modify' just upload. We have around 4,000 products so I am wondering if the option is not showing up because we have too many products or if this modify option no longer exists? It has been a while since we have had to upload multiple new products. 

If I download my entire library and reload I will lose my images so this is not an option. 

[Moly_Capital]

I’m ‘pretty’ sure (but please try with just one item) that if you download the catalogue and don’t edit the unique identifier, when you upload it will edit the exisiting item not create a new one