Keep in mind one thing, the clerics of the realm may choose to heal you or they may not be able to do so. If a cleric does not heal you do not demand heals and continue pestering the player for them. It is entirely possible that they are not at their terminal (idle) or that they are in combat and are missing the messages.
There is also a command which can be used to either repay a cleric for a heal, or to encourage that cleric to heal you. That command is 'tithe'. This will allow you to transfer some gold to the cleric of your choice.