I've been in a horrible reading slump for years. I was fine with audiobooks and podcasts but just couldn't concentrate on reading.
Finally I've found that Agatha Christie novels hold my attention - they are fast paced, not overly complicated, and got me interacting with the story as I played detective while taking notes on the clues in the story.
Now that my reading muscle memory is coming back, I'm able to branch out to more complex books.
I recommend 'The Chronicles of St. Mary's' by Jodi Taylor.
It's light, fun (hilarious sometimes) and my favourite when I feel down. Mostly I read it, but the audiobooks are fine too.