Bloons TD6+ game data lost after accidental reset

Hi,

Whilst playing "Bloons td6+" on my iPad, my 8yo son accidentally pressed "ok" when a pop- up notification asking him whether he wanted to reset the game came up (well that's what he thinks it said because he was too quick to press "ok" without properly reading the message). Now all his previous progress is lost and it's started a new game. Is there a way to retrieve/restore previous data? He is on my apple account. I don't think I have a Kiwi account (Bloons developer).

Thanks in advance.