Discover and MasterCard payment method doesn't work in real order simulation or test mode

Payments + Shipping & Fulfilment

Topic summary

Discover and MasterCard payments fail on checkout and in test mode with Shopify Payments, while Visa and AMEX work. The checkout shows “There Was An Issue Processing Your Payment. Try Again Or Use A Different Payment Method.”

In abandoned orders logs, the error “undefined method rate for nil:NilClass” appears, including when using Apple Pay with Discover/MasterCard. (This is a Ruby error indicating the code tried to call a method on a missing object.)

Support contact to Shopify has not resolved the issue after nearly a month.

Recent update: One user resolved the same problem by properly selecting an underlying plan during a $1/month trial.

  • Navigate: Settings → Plans → Pick a plan
  • Select the Basic plan
  • Confirm the green button changes from “Select Basic” to “Review my plan”
    After this, Discover/MasterCard payments began working for them.

Status: No confirmation from the original reporter that this fix worked; the discussion remains open. Key implication: account plan selection during trial may affect card processing, impacting both live and test mode.

Summarized with AI on January 28. AI used: gpt-5.
1

I’m attempting to do test orders on my website by using a Discover and Master card. It won’t work. It works fine with Visa and AMEX. The checkout page would give the error “There Was An Issue Processing Your Payment. Try Again Or Use A Different Payment Method.” These are all with Shopify Payments.

  • Manual Credit Card: In the abandoned orders, it shows error “undefined method `rate’ for nil:NilClass”. I can’t find what the issue is with this anywhere online.
  • ApplePay (with Discover or MasterCard): In the abandoned orders, same error above “undefined method `rate’ for nil:NilClass”.
  • Test Mode: Also doesn’t work.

Does anyone know why this is?

2

I’m still having this issue and it’s been almost a month since I posted. I contacted customer service and I feel like I’m talking to them in circles constantly.

3

I just had the same issue. I was on a $1/month trial plan, and somehow it hadn’t selected an underlying plan.

I went to settings → Plans → Pick a plan, and selected the basic plan.

Make sure it changes the text in the green button from “Select Basic” to “Review my plan” as confirmation that you successfully selected a plan.

After that the issue disappeared.

Hope it works for you too!