Sounds like you should take the advice already given. The cameras are unbelievably unlikely to have been hacked. What is much more likely is that your credentials have been compromised. If you haven’t done it yet, you should undertake a review of your security. Change any and all passwords relating to your online presence, as @Austin_Cox suggested a few posts ago, using a secure password generator.
To do this in a secure way, you should start with a factory reset of your phone, and start again with an entirely new account that you create whilst starting the phone, as you did for the first time. From there, do not enable WiFi, use only 4G, that way it is impossible for your phone to be compromised. Use that ‘as new’ phone, with its own new password, only on 4G, to change all of your other online passwords, including Blink. If the 4G network is compromised, for your phone or SIM’s unique identities, their IMEI numbers, then we are all in serious trouble, so you can trust that. Yes a new account is a pain in the neck, because you cannot easily restore from backup, but this is a small price to pay to be certain of your security. If you have lots of pictures, manually back them up to a PC or tablet, being sure to transfer only the pictures themselves. I suggest getting your apps again manually, because if you try to use something that does it for you, you don’t know what else you are importing.
Thereafter nothing you do in terms of resetting can be seen, because you are connecting over this secure, uncompromised, 4G network. Once all are done, if it continues, you will know that whatever is creating these false alerts it is not someone logged into your account, trying to spy on you, and you will be able to contact Blink support and explain that it is impossible for someone to have your Blink credentials, and that they should explain to you what is triggering these live views.
Not that I have ever been through anything like this, but it’s what I would do if ever I felt threatened in a similar way.