BUG- Downloaded maps now blurry

I have the pro app so I can use specific maps like Trails Illustrated. I had downloaded the Trails Illustrated layer about a year ago in high resolution and it has always worked fine until recently. Now random squares are blurry until I zoom in or out- doesn't all seem to be the same. I have tried turning off cell data (although it doesn't seem to matter if I have a connection or not), I've tried re-downloading the map, and this seems to be the only layer doing this. I do need the Trails Illustrated layer for work purposes.