Can you share a snippet of how you use the API? I'm trying to use Excel and its acting fubar for me. If you can show your snipped for one currency, I can pretty much make it work for the other 200 currencies I'm invested in.
My setup is on Google Sheets.
The script is slightly modified of one I found googling how to import json feeds.
https://pastebin.com/raw/gyzX8Q1A - this goes to tools > script editor
=IMPORTJSON("
https://api.coinmarketcap.com/v1/ticker/casinocoin/?convert=EUR","price_eur",$I$1) - this goes in cell where you want price to be stored. Additionally I put an image with assigned script REFRESHCMC which increments I1 cell for me (you can see it in bottom of pastebin) and forces IMPORTJSON to recalculate, effectively refreshing data when I click on image.