In the current version of the plugin, a range field excludes all posts that have no meta data for that meta key (WordPress doesn’t have meta keys with empty values on posts, it does not have that meta key at all for the post.
If you manually set defaults (From and To) that are above and below the actual values, you then need to use our Edit Query Arguments filter to remove that field from the arguments by testing what values are there to look for both of those default values.
It might also be possible to edit the URL to look for the part of the string that is the default for that field, and remove it. Both of these filters are detailed here:
https://searchandfilter.com/documentation/action-filter-reference/
I might be inclined to try the URL route first. You can try it yourself. Do the search and then manually edit the URL in the browser to remove that part.
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