I've been trying to print a case for a raspberry pi setup and anything I try to print that is tall seems to lose definition and get "stringy" on the final layers of the print. I'm printing with PLA and using SLiC3R. Tried changing temps, but nothing seems to matter.

I'm new to 3D printing, so I hope I can find a few tips and suggestions here on how to fix the issue.

Thanks in advance!