Unlike Peatio v2.3, Peatio v2.4 stores wallets settings in Vault. Since all settings should be moved to Vault, we need to recreate wallets in Peatio. To do this, follow these steps:
Execute into Rails Console and run:
    result = Wallet.all.map { |m| m.attributes.except('created_at', 'updated_at') }.map { |r| r.transform_values! { |v| v.is_a?(BigDecimal) ? v.to_f : v } }
    result.each do |w|
      w.except!('settings_encrypted', 'id')
      w['settings'] = Wallet.find_by(address: w['address']).settings
      w['kind'] = w['kind'].to_s
    end
    File.open("config/seed/wallets_backup.yml","w") do |file|
       file.write result.to_yaml
    end
    Wallet.delete_all
Put content of the config/seed/wallets_backup.yml in the config/seed/wallets.yml.
Change the Peatio version.
Run rake db:migrate db:seed. It will migrate DB and seed wallets into Peatio.