Please help! I've attached screenshots above.
Thank you for your posts and screen shots, and I apologize for the late reply.
From your screen shots, nothing looks out of the ordinary, and it is still difficult to determine what may be the cause.
To check the field itself, create a new Layout with just the Store Order Number field. See if you are able to enter data into this field on this new layout. If this works, then you can focus on the original layout. If this fails, the field may be damaged.
I'm assuming this works correctly on your Desktop machine?
I know several weeks have passed since your posts, so if you have since found a solution, please post here in case others encounter a similar issue so they can benefit from your solution.
I've set this thread to contact me when you post again.