Tired Starter: Refresh or Restart?

I have a starter that I've been regularly baking with for around 6 years. Unfortunately, when the pandemic hit I had a very difficult time finding flour! As a result, my starter went beyond the normal one week in the fridge breaks (Maybe a few months passed without a feeding-whoops!). Since then, I have not been able to get it to bounce back to its old strength. 

Before the pandemic I was feeding it around every 12 hours when I was baking, and then it would go in the fridge for 4-7 days until I was baking again. I would see some sluggishness at the first feeding, but normally by feeding 2 it would be thriving. 

I've tried feeding at 12 hour intervals for around a month, and it is not producing like it used to. 

So, my question is: Is it worth nursing this starter back to its old self, or should I start afresh? And what steps can I take to re-nourish my old starter? I am sort of attached to it, and starting all over again is sort of sad...

Any advice would be welcome!