Jesus is talking to a group of people about what they as individuals should and should not do. All occurrences of "you" and "your" in verses 5 and 7 are plural; in verse 6 they are singular, but in some languages they may need to be plural. (See: [[rc://en/ta/man/translate/figs-you]])
Possible meanings are 1) the repetitions are useless. Alternate translation: "do not keep uselessly saying things over and over again" or 2) the words or sentences are meaningless. Alternate translation: "do not keeping repeating meaningless words"