Jesus is talking to a group of people about what they as individuals should or should not do. All occurrences of "you" and "your" are singular, though in some languages they may also need to be translated as plural. (See: [[rc://en/ta/man/jit/figs-you]])
Possible meanings are 1) no one can see God. Alternate translation: "Father, who is invisible" or 2) God is with that person who fasts secretly. Alternate translation: "Father, who is with you in private" See how you translated this in [Matthew 6:6](../06/06.md).