Hacked by previous company/management

I recently left a toxic workplace due to poor management. Prior to leaving, I suspected that I was hacked by certain managers when they started hinting at my personal life and projects. For context, I was a remote worker and kept my personal life out of work conversations; so it was a bit odd when they started mentioning stuff. I also never used my work laptop for anything personal and the only work app I had on my personal phone was my work email and zoom account. I'm not in tech/government or some other serious industry. I just had immature management who loves to steal my ideas and knows that I have evidence to pursue a legal case with them.

I know they're spying on me and have my router, computer, and phone hacked. At first, I thought it was because I work remotely, so they have access to my network, but even after I've left, they somehow are still able to access my searches, see what I'm doing, and hear my phone calls.

While I was employed there, one of the weirdest things that tipped me off was when one of them rewrote an idea I was personally working on, on their social media. But I've only written that in my personal ChatGPT and Claude account, so I mentioned in both chatbot that they might've hacked me and a week later, a portion of that conversation was deleted in both my ChatGPT and Claude account. I usually use the apps on my phone and am usually logged in. I'm not anymore, but I'm wondering if it's possible for a hacker to even delete chat messages in ChatGPT and Claude? If not, would it have been an insider? My previous company is implementing AI, so they have corporate accounts.

Another weird situation I had (after I left) was when they also knew about what I was working on in Tails. I've been doing a lot of research on cyber security and read that an infected device shouldn't affect tails. But I was connected to my home network when I used it.

At this point, I'm not really sure what to do anymore. I've factory reset my router, computer, and phone multiple times. I have dns and mfa/yubikey set up, use duckduckgo/brave and keyscrambler. I have paid bitdefender on all my devices, but it never scanned anything malicious. I've upgraded to using Ubiquiti dream router 7 and have its securities on. I check the logs every other day and there's never anything weird except for a packet loss detection that happens every other day around the AMs when no one's usually on.

I have 0 background in tech/cyber, but have done a lot of research in hardening my devices. I'm hoping someone can help me make sense of all this and provide some insights into what I'm missing or what I can do next. TIA.