reset glitch (v4)

Hello,

I bought a tamagotchi (v4) a few days ago, and he ran out of battery yesterday. When I changed the battery, I selected "download" so he was there, and all his stats were still like before. But I lost all my money and items. He grew as an adult today and he's lovely but I've noticed that it says he is only 2 years old, while he was born on 30/04.

I did a little researches but I found nothing about this bug, does it happen often, and can I do something about it? And do you think my tamagotchi will age normally for the next days? 

Thank you for your help! 

Hello there and welcome to TamaTalk!  

The age doesn't sync with their growth stage, meaning when they grow up it will take some time to age. Regarding the money and the stuff, I never really heard about this, there’s a possibility that when it reset it didn’t save anything before that’s why everything was gone. 
 

Thank you!  

And I don't know if it is possible to answer, but do you think that it could be a problem with my tamagotchi and there is a risk that it happens again when I have to change the battery later?