It appears that your wallet address has been compromised. If your Pi is transferable, it is at risk of being stolen.
Based on this experience, your wallet has likely been hacked, and your coins are vulnerable to scams.

The  solution is to :
Go to your pi browser and click on the wallet
Generate a new wallet address.
 Securely store your key phrases (write them down or save them in a secure location).

 You can also enable fingerprint authentication for added security
Lastly, do away with your first wallet and start to make use of new wallet generated keys.