My boyfriend got grounded what do I do?

so my boyfriend and i have extremely strict parents. and well we get our phones taken away very frequently. but my boyfriend lost his parents trust because of something he did a while ago and everytime he gets grounded now he gets his phone taken for a very long time, and we can't text. it sucks because of quarantine and i really miss him. he stole his phone a while ago to tell me he misses me and honestly i feel bad for him and i know that his parents are trying to discipline him but i miss him. i can't send him letters because i am sure his mom will open them and my parents dont allow it, so what do you sugges i do about this?
My boyfriend got grounded what do I do?
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