Some authors don't want to deal with certain fans, simple reason: Those fans annoy them.
She keeps on blocking you because you are disrespecting her boundaries, she doesn't want you to comment, she doesn't like what you comment, she doesn't like the engagement she receives from you, she probably has hinted that to you in her replies or by ignoring you, yet you don't get it, she blocks you, yet you go making multi-accounts to keep getting on her space, you are being overbearing, dense, forcing your way into her, forcing an exchange with her.
You're basically putting what you want and how you feel first, instead of understanding your freedom is limited by the consent and freedom of the other, you're totally ignoring how she feels, how you are making her feel and your behavior is only making things worse.
Why do you even need to engage so much with this author? Literally, most readers I've seen just read the story and call it a day, if she has a huge number of people commenting, asking and such, then one number less isn't important, especially when her patience and tolerance is also limited because she is human too. She is the creator and center of the community she builds, she can decide who has the privilege, set the limits and all. You either accept that or overfixate in a different creator that has no issue with your (toxic) fan attitude.