My first impression from the adhesion issue (which doesn't appear to be the main issue of this post) is that you may need to clean your build plate. But considering it was relatively good as it is, I assume you did and the few spots may just be accidental touches to the surface. In either case, their guide is here: https://wiki.bambulab.com/en/filament-acc/acc/pei-plate-clean-guide
As for the extrusion issue - considering the apparent randomness of it my guess would be either an issue with the filament or a partial clog.
I hate Comcast/Xfinity with such a passion I tell myself if I had the same hatred for a person I'd be in jail for murder.
Not only did they impose their "trial data caps" in my area and charge me out the ass for going over 2TB a month, I acceded once to being upsold and was told it was completely reversible within a month. After realizing the sales shithead lied to me about the features, I called to revert. Guess what? They couldn't. It wasn't something they could do. Fortunately I recorded all my calls, but even with that it took me more than 30 hours of phone and chat time to get it fixed, and the agent who finally helped me had to setup a recurring account credit to fix it. Absolutely horrid. She basically clarified, without saying it outright, that the sales shithead lied to my face because they're practically encouraged to.
Long story short my home purchase decision was influenced greatly by those shitheads not being in the area, and just seeing an ad makes me want to vandalize it. It's the only thing I hate with this much passion.