Lightning Opportunity Product Sort Button is Missing?
Did you try clicking on the column names in related list? Like below.
That should help you sort based on the fields you need.
Next time you go into Products is reverts back to the default - Sorted by Sort Order, Total Price, Opportunity Product Name
Users want it to sort by the order they enter each product not product name aphabetically, as it seems to list them.
Is there any way to change this default ordering as in screen shot below in lightning?