With these it helps Forgive me if Google Analytics has some regex standards which I am overlooking but is it possible that your regex is failing because it does not account for the start of the whole of the URL? Adding .* to either end of your regex may help. It also looks like your regex is over-complex for the conditions you have described. Could a simpler match be :
Shopify Product page regex match in Google Analytics Goal Funnel
Does that help Some observations: /* looks dubious as a regular expression for Index. It will match a slash character any number of times, including zero times. In other words, it will also match nothing - see demo. As others have pointed out, to match a literal question mark, it needs to be escaped by preceding with a backslash - so \? instead of ?. As far as I can tell, Availability(\?.*|$) ought to work - see demo. Are you sure the problem isn't elsewhere? The final three regular expressions may or may not be sufficient - if there might be the possibility of something like /Booking/Indexer for example, the /Booking/Index.* regular expression would match this, which could be wrong - see demo. To rule this out, consider an alternative such as /Booking/Index([/?].*|$) - see demo.