Google Authenticator on Apple devices, certain secrets are not valid

Question

We\'ve incorporated two factor authentication into one of our applications using Google Authenticator. In QA, something really weird turned up. While I managed to fix it,

Answer 1

I also have a problem with this.

This link is valid

otpauth://totp/xxx.yyy:usertest009%40xxx.yyy?secret=CC5FCZNWTKNTOVN6&period=30&digits=6&algorithm=SHA1&issuer=xxx.yyy

But with diff secret key will make it invalid

otpauth://totp/xxx.yyy:usertest009%40xxx.yyy?secret=PBUPKS3SLJAP9V2T&period=30&digits=6&algorithm=SHA1&issuer=xxx.yyy

I found out the problems The secret key must be base32 string. I am using NodeJS, so I use speakeasy to create secret String base32. It works now.