Can I use 2PS Plus Account online even though I have one?

I have 3 playstation accounts, but suddenly an error occurred and I should log in again, but it has been a while since I created this 1 account for which the PS Plus subscription was geared and I know the email Address and password no longer, but I still knew everything from the second account. Can I still use the PS Plus subscription on the other two accounts? The subscription runs for a few more months and would find it annoying if I had to buy a new Plus subscription now.

Can you still access the account? If no, then it sucks: / If so, you can activate it as your primary ps4 in the settings. If that's the case and you don't know how to set it up, just google it. There are enough tutorials.