from your screen provided in comment, you passed one property you don't access to it which is data
So just add property data before FLUX
JSON.parse(d).FLUX.quote.USD.price;
^data.FLUX.quote.USD.price;
From the image of the log the object seems incomplete at the end, did you try to use JSON.stringify(d) to see if there are any errors on the json object? or copy the response on https://jsonlint.com to check?
Because the error message points that the parse doesn't find a valid json object, maybe that is the whole point.
And the other tip is to try to store the value of JSON.parse in an variable before trying to access his values.