SharePoint 2019 FBA set default password

We have used FBA Membership for our SharePoint Application. We have user Membership.CreateUser() Method to create the user.
When user logged in, always we get error in Membership.ValidateUser().
So always we need to do reset password from the FBA User Management Page.

Could you please advise is anywhere we can set default password for Membership FBA

That sounds strange. If you have to reset the password using the FBA Pack - I assume creating a user using the FBA Pack also works fine? Creating a user with the FBA Pack uses membership.CreateUser (and sets the password with it) - so it should work exactly the same.

I’d maybe suggest debugging both the fba pack and your code to see the differences in the createuser call to see what’s going on.

Do you maybe have multiple membership providers and are calling CreateUser from the wrong one?