Coil pack failures

I have a MX5 1.6 which was registered in April 2000 and I’ve owned since 2003. I’ve had no real issues with it and don’t do many miles.
Even though it’s 20 years old it’s still under 70,000 miles. I love my car but about 18 months ago my coil pack failed and I had a new one fitted.
It’s failed again after only quite minimal use. I’m obviously getting another new coil pack fitted but wondered if anyone had any ideas what might be causing it to keep failing. I know that leaving the ignition on without the engine running will burn out the built in ignition amplifier in the coil and very rarely do I do that so I’m pretty sure that isn’t the underlying problem.
Any ideas.

The MK2/MK2.5 1.6 has the weakest coilpack of all MX5 cars.
Typical reason for failure is ignition left on without engine running, for example during MOT test. This causes buildup of charge without discharge and they don’t like it!
I guess you bought aftermarket; If so should still be under guarantee?
I sell original Mazda coilpacks but to be honest thought the aftermarket units were reasonably good nowadays.
Important to avoid misfires on these cars as unburnt fuel will get onto the cat, ignite and superheat the core.

Thanks - no it wasn’t under guarantee and I have already got another one but good to know you sell them for the future.
I don’t typically have the ignition on without the engine running and am so surprised that it would fail so quickly. Any other ideas as to what could be causing it to fail. I understand that the underlying issues could be from the earth points underneath the headlamps which can get rusty causing a bad earth so I’ll check that out but wondering if anyone knows of anything else I should check.