It works if you include "www". It doesn't if you don't.
We are all accustomed these days to including/excluding "www" at will, since every major site will redirect you to the correct landing page, but www is actually a subdomain. Type in
www.bitcointalk.org and you will redirected to
https://bitcointalk.org. Type in
reddit.com, and you will be redirected to
www.reddit.com. The owner of this site simply hasn't configured their top level domain to redirect to the www subdomain.
It's a DNS issue
If you look up cryptowaves.app you get : 162.255.119.113 which goes to namecheap where the domain is registered.
If you look up:
www.cryptowaves.app you get all the information for heroku which is where it runs.
alias = powerful-pumpkin-jp0rxzcpyumcnz5az60yqpuq.herokudns.com.
powerful-pumpkin-jp0rxzcpyumcnz5az60yqpuq.herokudns.com.
3.220.57.224
powerful-pumpkin-jp0rxzcpyumcnz5az60yqpuq.herokudns.com.
3.232.242.170
powerful-pumpkin-jp0rxzcpyumcnz5az60yqpuq.herokudns.com.
52.20.78.240
powerful-pumpkin-jp0rxzcpyumcnz5az60yqpuq.herokudns.com.
54.91.59.199
As a side comment heroku is owned and run by salesforce which has had some security issues (who hasn't) but also some privacy issues.
Just because the developer says it's secure you still don't know what is going on with the back end.
-Dave