Entra SSO with Google as IdP

I tried to configure SSO between Entra and Google IdP. Here is the documentation of the steps I followed: https://apps.google.com/supportwidget/articlehome?hl=en&article_url=https%3A%2F%2Fsupport.google.com%2Fa%2Fanswer%2F6363817%3Fhl%3Den&assistant_id=generic-unu&product_context=6363817&product_name=UnuFlow&trigger_context=a

In step 3, namely Set up Office 365 as a SAML Service Provider (SP), where I was asked to execute the script on the M365 side, it failed.
Here is the script I used (of course the value of each variable has been adjusted):

$dom = "ourDomain.com"

$BrandName = "Whatever you want it to be"

$LogOnUrl = GoogleSSOURL

$LogOffUrl = "https://accounts.google.com/logout"

$ecpUrl = GoogleSSOURL

$MyURI = GoogleEntityID

$MySigningCert = CertFromGoogle 

$Protocol = "SAMLP"

Set-MsolDomainAuthentication -DomainName $dom -FederationBrandName $BrandName -Authentication Federated -PassiveLogOnUri $LogOnUrl -ActiveLogOnUri $ecpUrl -SigningCertificate $MySigningCert -IssuerUri $MyURI -LogOffUri $LogOffUrl -PreferredAuthenticationProtocol $Protocol

The Result :

I don't know why this is happening, please advise thank you.