If the player is breaking the ores with nothing, nothing happends.

[habbic]

on mine:
    if event-block is coal ore or redstone ore or gold ore or lapis lazuli ore:
        if player's held item is not iron pickaxe:
            set event-block to bedrock
            wait 1.5 seconds
            send action bar "&c&lYou got nothing seems weird..."
        else:
            if player's held item is iron pickaxe:
                clear drops
                send action bar "&e&lAdded Credits to your Account you have %{credits::%player's uuid%}%"
                add 10 or 20 or 15 or 50 or 30 to {credits::%player's uuid%}
                set event-block to bedrock
                wait 1.5 seconds
                set event-block to coal ore or redstone ore or gold ore or lapis lazuli ore

 

[Gryphon2029]

If you use 'on mine', only events where the broken block dropped something will call the trigger.

on break:
    if event-block is not coal ore or redstone ore or gold ore or lapis lazuli ore:
        stop
    if player's held item is not iron pickaxe:
        cancel event
        set event-block to bedrock
        send action bar "&c&lYou got nothing seems weird..."
    else:
        cancel event
        send action bar "&e&lAdded Credits to your Account you have %{credits::%player's uuid%}%"
        add 10 or 20 or 15 or 50 or 30 to {credits::%player's uuid%}
        set event-block to bedrock
    wait 1.5 seconds
    set event-block to coal ore or redstone ore or gold ore or lapis lazuli ore