Company logo not showing on invoice + can’t remove link to logo

Two company logo issues:

1. I have uploaded a company logo to the media library and pasted the URL into the invoice template header options. Have tried both PNG and JPG, but only gets a red cross on the PDF.

2. Since I couldn’t make it work I decided to remove the link from the input field and just use the company name, but now I can’t get rid of it again. I have emptied the field with the logo-URL and pressed save, but as soon as the save is done, the link is back there. And I still just have a red cross on the PDF.