Has anyone received this checkout error

[SKCandleCo]

I set up the online website for customer shopping. However when customers go to check out there is a box that gives this message: Unfortunately since your order is already set as shipping, you cannot add other items under another fulfillment method. Please remove the items or update your selected fulfillment method.

My only method for fulfillment is shipping. Does anyone know how to fix this error?

[JJ_]

Hello there @SKCandleCo and welcome to the Seller Community

I took a closer look at your items and some of them appear to have the Pickup fulfillment method assigned as well as the shipping. 
I recommend revisiting your items in Square Online and making sure that under the fulfillment method, only Shipping is assigned.

I hope this information is helpful!