You are seeing such behavior due to the remnant data on your phone which will be erased upon reset.
You will need to update your Argent app to the latest version, then perform wallet recovery according to the process below rather than restoring it from the common iCloud app backup.
If you still have access to your old phone, you can proceed with off-chain recovery by:
1. Updating the app on the old device to the latest version.
2. Saving the encrypted recovery kit as described here.
3. Proceeding with off-chain recovery as described here.
If you don't have access to old device and no encrypted recovery kit saved previously, you will need to recover your wallet on-chain with Vault/guardians, restoring from iCloud backup will not work as your private key never leaves the device unencrypted. The recovery is a set of on-chain transactions that require network fee to be paid. You can use ETH, DAI, USDC, USDT to pay network fees in your Argent wallet. You can also find more details on the recovery network fee here.
You can recover on-chain your wallet by following this guide.