Hey guys, sorry for out of topic.
I have a Panasonic water heater with push on/off lever installed.
Recently there are water leaking/dripping out from the shower head when the push lever was turned off.

If I turned off the faucet on the wall, the water stopped dripping. So it seemed like the push lever is starting to malfunction.

Do you guys know this can be repaired? I asked the service center as well as few plumbers, all suggesting changing a new unit.

Thanks.