The short answer
Understand the system before choosing an action.
When a debt becomes delinquent, the original creditor may contact the consumer, restrict or close the account, report account status, charge fees or interest under the agreement, place or sell the account to a collector, or consider legal action. The exact path, timing, rights, and consequences depend on the debt, agreement, jurisdiction, parties, and current law.
Financial Learning Cafe explains the subject. Your current agreement, official sources, facts, jurisdiction, and appropriately qualified professionals control the decision.