Hera cursed the nymph with the voice of the echo, doomed to repeat the last words of what was said before, as punishment for distracting her with chatter.
Echo, though it was more to do with Echo distracting Hera while Zeus lay with other lovers.
In the story of Echo and Narcissus, Echo annoys Hera by distracting her with her chatter when Hera is searching for Zeus, who is often unfaithful. Echo, a nymph cursed to only repeat the last words spoken to her, uses her gift of conversation to mislead Hera, ultimately angering her. This leads Hera to punish Echo by taking away her ability to speak freely, leaving her only able to echo the words of others.
Echo offended the goddess Hera by keeping her in conversation, thus preventing her from spying on one of Zeus' amours. To punish Echo, Hera deprived him of speech, except for the ability to repeat the last words of another.
Hera caught Echo and Zeus having sex
Echo was a nymph that helped Hera out normally. When Hera went looking for Zeus, Echo stopped her with chattering. Zeus had an affair and Hera cursed poor Echo, unabling her from making her own words. Which means she had to repeat.
Echo distracted Hera when Zeus was dating another woman. Her chatty personality made it hard for Hera to figure her out. She eventually did and cursed Echo.
Hera isn't involved directly in the myth of Narcissus, but she was involved with Echo. Echo had a bad habit of repeating things she'd been told in confidence, so to punish her, Hera took away her voice, making her only repeat things other people said. Later, Echo fell deeply in love with the human hunter Narcissus, but because she could only repeat what he said, he shunned her. After this she pined away until only her voice remained.
Echo.
That was Echo. She tried to hide Zeus from Hera when he was having a party with the nymphs. Hera was angry. So Hera only allowed Echo to repeat the last three words of what ever was said to Echo.
Echo
Hera
Echo