I had a concern regarding the Transactions for Membership 2 Pro

I can see users who have renewed their subscriptions, payed using the default PayPal standard gateway (Displayed as Billed), yet their account Payment Gateway shows " - No Gateway -" and their status is showing "Pending (activate on next payment)".
They are showing up under Expired under Members. I'm just confused as to the background process and time frame. Any help or information would be appreciated.

Thank you so much and Rock On!!!!