I'm worried about the white lines, and there's some divets in the middle too. The pictures I've seen online of other Hermanns all have super flat undershells.
I don’t personally see anything too worrying, lots of torts get those white lines, they’re no harm. Don’t suppose you’d be up for sharing a bit about your housing? We can make sure everything checks out for you
What are your temperatures like all over? Ie basking temp(directly under the bulb), overall day temps(middle and cooler side), night temps?
What kind of basking bulb is being used specifically? Packaging photos are good if you have any
Do you use indoor uv? If so what kind?
How’s humidity?
What’s his substrate?
What kind of monitoring do you have?
What’s his diet been like with you?
A photo of the full set up would be wonderful! Welcome to the forum