i cant get in my apple account because my sister stolen my rk key to open my account

every since my iPhone got cracked screen i cannot go in but still can use my Bluetooth data to my tablet just ok. but the problem is i cannot go in my account because i set it up for double security code. and now i cannot go in without my code number on my iPhone imessage. so please help me, so i can try use app on my tablet for at&t messages and all text message i had on my iPhone i know it still there. there are important message i need to get. and photo also

for my court.,

ios 9.3.5.