# Important to remember * The revised **itinerary must be booked to the corresponding booking classes**. TCP Exchanges & Refunds service is not using “Best Buy” (FQBB) transaction. * **Filed Fare** must be stored for each passenger separately. TCP Exchanges & Refunds service has the ability to copy the data from an already created Filed Fare for the first passenger to the masks for other passengers that have the same Fare and PTC (passenger type code) in order for the agent not to repeat the process for each passenger separately. * The **PNR** in Travelport+ (Smartpoint) **can be closed** because TCP Exchanges & Refunds service is totally independent of the system. * A new **endorsement** message, if filed with the Fare, is automatically stored and the agent can modify it or add an important notice. Each message can be separated by dash (-) . * In case of reissue of a **partly used ticket** (after departure) all segments including those already flown must be marked in order for the ticket to be recalculated from the origin. * The **exchange/reissue of IT tickets** – the original Fare and/or Equivalent must be entered manually by the agent because TCP Exchanges & Refunds service cannot read the Fare and/or Equivalent from the original ticket. * **Taxes** – unused taxes can be refunded or used for compensation of the Fare difference. New taxes or additionally paid taxes must be paid every time and cannot be compensated by unused taxes or residual Fare value. The agents can decide whether unused taxes will be refunded or not. * **Informative pricing** – if you would like to receive a new Fare calculation for information purposes only, it is necessary to create **new segments in** TCP Exchanges & Refunds service. Informative segment(s) are not stored in the PNR but can be booked by TCP Exchanges & Refunds service upon your confirmation – see the separate example. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://cee-systems.gitbook.io/tcp/overview/introduction/important-to-remember.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.