I had tons of layer separation and layer bonding issues when I first got MH Build Series PLA. The only color that seemed to print fine was the black (I bought White, Red, and Black). I was salty to say the least as I had heard great things about the filament and it is pretty cheap for a decent brand of filament. I did some searching to no avail so I said what the heck, why not throw it into my "PrintDry" (I say it in quotes because I turned a food dehydrator into a PrintDry for a total of 25 bucks). I put the MH Build white and red in it with another roll of PLA that needed dried and set it to 45C and let it go. I shut it off about 10 hours later, let it cool, and then put two of the spools into their ziploc desiccant bags and tried to print with the white. To my surprise it printed perfectly fine. The exact same slicing file that wouldn't bond layers together printed near flawlessly.
I don't know if the batches I got had a higher water content than they are supposed to or what, but ever since that day I ALWAYS throw my MH Build Series PLA into the "PrintDry" before I print with them for the first time or transfer them into their ziploc dessicant bags from their factory sealed bag.
If you don't have a "PrintDry", I would HIGHLY suggest you make one before you get into the Nylon game. Nylon absolutely LOVES its water and soaks it up far quicker than I ever thought it would. So much that I even built an airtight filament box to print Nylon from so that it can still be printed in a desiccant box. I had found that even average prints (~8 or so hours) would show a slight but noticeable difference from the base where the nylon was very dry to the top where it had soaked up water from the air, even a little bit of water seems to mess with most nylons. Good luck!