I may be completely wrong but it seems that the HTTP Binding doesn’t like the space (%20) in your URL
The next character after the space is L and the binding may be parsing that as a “Conversion” ?
Try to use caching to see if this goes away or try to escape the % character with another % or \
Found this: Http binding error, Invalid query - #6 by steve1 (from 3 years ago 
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