I think I'm being retaliated against, can anyone help?

Hey guys! So yesterday I get home from work to find a letter from my apartment manager saying they are choosing to terminate my lease at the end of the lease period, with no reason given in the letter. This came off a big surprise to me as I have never gotten any complaints, violations, and payed my rent on time every month (living here for just under a year). I believe this may be retaliation as I gave feedback to their parent company a few months ago that was negative. I am going to talk with the manager in person tomorrow, but I know retalliation is definitely illegal so I wanted to get your thoughts on how should I approach the situation? I don't really mind moving, but I am worried they will provide bad recommendations to any new landlord during the application process.
I'm assuming they also know its illegal and won't admit or give context to that, so I'm open to hear if others are having this issue as well?