'Pending Customer Approval' normally means that when the customer signed the Mandate form, they ticked the box to say that they require dual signatures, as seen in the screenshot below, but have not yet returned the form to GoCardless.
If you believe the customer has recently signed the mandate and it is pending customer approval due to the requirement of dual signatures, you can send them a reminder email from the GoCardless Dashboard. Details can be found here.
A restricted mandate relates back to when the 'Pay Now by GoCardless' button was available on Xero invoices. This allowed the customer to approve the invoice and pay. H
We always suggest that, if you are having trouble with the 'Pending Customer Approval' status, you cancel the customer's existing mandate (at GoCardless.com) and then send the customer a new sign up link.
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