Signs wont show after server restart

Hi there,

Today i made my own dedicated server and everything is working fine…

Except for the signs :frowning: when i restart my server all the designs on the signs are gone.
When i look into the folder where all the .png files are saved, all the files are there.
It just wont load them or something.

Does anyone know how to change it so it will show the signs?

Thanks!