In addition to the deadline for issuing reservations (TL), there are tariffs whose rule requires advance purchase at X days before departure (Advance Purchase).
This condition can be observed on the Fare Display via the “AP” indicator or in the fare rule, Cat 5/AP. ADVANCE RES/TKT, so it should always be consulted, under penalty of exceeding the issue period, the tariff will no longer be valid and is not allowed to issue.