Is the closing of the glass door in an internet cafe with a person inside, while other young men are present in the same cafe, considered a state of khalwa?

If entry to and exit from the hall are accessible to everyone without permission or suspicion, then it is not considered an unlawful seclusion (khalwa shar'iyya). The prohibited seclusion is the isolation of a man and a woman who are not mahram to each other, with no third person present. Or the isolation of a non-mahram woman with two or more men, because this does not prevent conspiracy to commit indecency. Seclusion between non-mahram individuals has been forbidden based on what was narrated from the Prophet, peace and blessings be upon him: "No man should seclude himself with a woman unless there is a mahram with her," and "No man secludes himself with a woman, for verily Satan is the third of them."