Fresco print quality 300 dpi but blurred

I illustrate using Adobe Fresco on iPad pro - I have drawn an illustration using the vector brushes, have set the dpi to 300 under the settings / print, but when my printer has gone to print it for me, they have opened it in Photoshop, the edges are not crisp and its slightly blurred. What am I doing wrong! Its driving me insane and I need these printed for a client ASAP 

Thanks in advance 🙂