David Kimura PRO said 5 months ago on Stripe Billing Portal :
  marvinick You should be able to create the plan via the code which is what I normally do. See if this helps.

plans = [
  {
    product: {
      name: 'Annual',
      id: 'annual'
    },
    id: 'annual',
    interval: 'year',
    currency: 'usd',
    amount: 1900
  },
].freeze

plans.each do |plan|
  Stripe::Plan.create(plan)
rescue Stripe::InvalidRequestError => e
  puts e.inspect
  next
end