Hello,
Just reporting back that I bought a new high endurance microSD card and flashed and installed it on the node/miner and all is well. Back to mining and syncing blockchain. Thanks for the help.

It is very possible that you have a microSD wear issue. I'd even just go get a new microSD after 2 years, to be honest. Look for high endurance models like Samsung Pro Endurance or an equivalent by SanDisk. Normal microSD cards are often made for just a few 100,000 write cycles, which can be exceeded quickly when they're used as a single board computer's main drive, where you might get a lot of writes in some areas of the memory.

Re-flashing can be a good temporary fix, but you'll run into similar issues much sooner than if you were to just get a new card.

You could still use the old / worn microSD for less 'mission-critical' stuff.
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