Tudor Harrods smudge on glass

[khalifam]

Hey all,

Struggling to post this, hope it comes up now.

My Tudor Black Bay Harrods has a smudge like mark on the glass... I gave it a wipe and still remained. Today I attempted to give it a proper wipe however, the smudge still remains. I have run my finger and nail across the glass/smudge however, nothing obvious i.e. it's not a scratch... You know you'd run your mail across a scratch on your smart phone and you can feel it? Nothing like that... Any ideas?

Sent from my SM-N960F using Tapatalk