I tried to view the wallet but such amount is not found on the Tronscan, and if such amount is found there you have to be sure it's not fake usdt as many token is regularly created on the tron network. be guided and be very careful.
Now if you found such amount do you flash back to know if you make such transaction or having that same amount before since you created the wallet?
if YES then is yours, If NO you have to write to support about the development on your wallet this shows how transparent you are.