The URL of a gift list is the combination of all the SKUs selected when creating the list. However, URLs with more than 7 thousand characters are not indexed by Solr – the indexing system used by VTEX.
This limitation is not directly related to the number of items in a list, but to the size of the URL. I.e., you can have lists with more products that will not time out with the indexer.
Select a large number of items for a list so that the resulting URL has more than 7 thousand characters.
If possible, edit the list and reduce the number of items selected.
If you cannot access the list, contact VTEX support and ask for it to be deleted.