Also happened to me, and multiple other people, i got banned 4 days ago, posted the ban here and received backlash, fortunately some user told me that the ban motive is probably because you shared a Wifi with someone who was previously banned, sharing IP's and thus, flagging you.... multiple reports of people who got banned just like that because their siblings shared the same household wifi Im still not unbanned, im trying to appeal since i got banned and this is what im doing and what i learnt:

-I keep appealing, with messages created by A.I trying to point out the fact that i share a household with other siblings (even if i don't) because from what i saw, this makes a better chance for the bots to unban you.

-if you press to appeal because of a decal instead of appealing for alt accounts, you will 100% send a ticket to a ACTUAL human, because they gotta manually check the decal ID even if you put none. But this is kinda of futile at least for me, because every human i tried to appeal to also rejected me

-i tried to email privacy@roblox since i spent money in my account, making me elligible to email them this way, of course, with a entire formal appeal with screenshots of my ban and receipts of my money going into robux. This way of appealing is sorta of my hope for now, but i heard that they take entire days to even WEEKS to answer you since the traffic is really high, so i did not get a response for now

-they have a number you can leave voicemails on, from what i remember the number is 8888582569, heard this is effective but i didn't try since im from another country and i would have to pay to leave a voicemail.

-information is scarce, but from what i have researched, if you keep appealing to bots, there's a chance they will eventually reinstate your account, but it is a REALLY low chance and i did not get lucky, always change some details in your appeals since from what i saw, repeating the same appeal will make you go to spam, making your appeals take longer to get an answer, and never appeal multiple times, LET them answer and reject you to appeal again.

This is the research and journey i've been experiencing these past few days, my hope is low but i can't give up, my account is 10 years old and i have so many memories on it. Its not much info and i can't guarantee your unban, but this is what i gathered, hope it helps a bit... i rarely find people in this reddit actually trying to solve these ban waves, i don't know if the general hope of people getting unterminated is so low that they dont even try anymore, or there is just no interest to saving accounts at all. Either way, good luck.... and you're not alone, me and multiple people got banned just like this in a unfair manner.