Even If you've entered your username and password correctly inside Vidently but still getting error which says "Error Loading Vidently Club. Please fill/check username and password inside settings to access the online slides!" when you try opening saved projects or try adding a scene.
Open up Settings. Enter your Explaindio Member Account email address instead of the username.
Please note that, this is the same email ID you've used to sign-up for Vidently and/or you used in your Explaindio Membership area here: https://account.explaindio.com/in/member inside your customer profile:
Enter your replace your username with your sign-up email ID.
Close Settings and restart the software.