You just have to recover your seed (Passphrase) in the settings, then try to detach the wallet (button in red at the bottom of the settings) if it works or not, uninstall the application & reinstall it there by entering your seed.

If you have lost your device, you can restore your account to a new device by returning your seed.

If the nodes your staking provider have not been chosen by the blockchain, you do not receive any rewards because this does not work for the security of the blockchain.

Your friends must be visible (Check privacy settings) + Be active the last two days.

Once you've claimed your @herotag, you can't edit it anymore. Since the herotag uses Elrond Distributed Name Service (EDNS) and is registered on the blockchain.

Maiar is free to download and use. However, the MultiversX network has minimal fees (as low as $ 0.001 per transaction) associated with payments in order to ensure the security and speed of transactions.

Yes you can use your xPortal seed (Application) to connect to the MultiversX Wallet extension. However, it is recommended for security to separate these wallets.

Yes you can, but it is however recommended for security to separate these wallets.

Just use the app, make transactions, sponsored friends or members of his community.

YES, You can earn EGLD each time your referral uses the application (by making transactions) you have the details in the settings => Referral. These rewards are distributed every Monday. (Ref: How does Inviting and Earning work ?)