Most budgeting apps only track your money, so missing a payment is dealt with by the company you were meant to pay, such as a lender, utility provider or landlord. If you mean the app’s own subscription, it may retry the payment, restrict features or cancel the subscription, depending on its terms. A missed loan or credit-card payment could lead to charges or credit-file reporting, subject to the provider’s policy and your circumstances. Check the app and provider’s terms, contact the payee promptly, and use MoneyHelper or an FCA-authorised debt adviser if you are struggling.