What warning did Phoebus Apollo give Achilles before he went to battle with Hector?

Before Achilles faced Hector, Phoebus Apollo warned him that he should be cautious, as fate had decreed that he would die at the hands of Hector. Apollo, a divine figure associated with prophecy and knowledge, emphasized the inescapable nature of fate and the inevitability of death in battle. Despite the warning, Achilles' desire for vengeance drove him to confront Hector, ultimately leading to both their tragic fates.