Thank you, I've updated everything, but we went full circle, I do not think the plugin version is the issue, or the api version, because then, every account would fail. A year an a half ago (same problem) you've accessed the account and told me the exact same thing.
But after I've updated everything I continued having the same issue. It's not something that went out-of-whack recently, it's been happening for over a year. Big mystery!

Also the webhook signing secret, was correct. Again, I would think that if that was the problem, then every subscription will have that problem, but it's only a few accounts.

I will continue to check, but I would like to know what procedure I should follow with those accounts for them to sync back?

What I'm doing is I'm reactivating the account manually, then, I go to subscriptions, click on the subscription id, and from there I set back the Auto renew type to "Mandatory" Autorecurring type to "Autoreccurring with notifications."

But I haven't had any luck so far, the following cycle, the system "expires" the status, set the auto renew type back to manual and the autoreccuring type back to "Not Autorecurring." Very annoying!

Any advice?

Thank you for your patience.

1,000 thanks for helping me find the issue, and for making things easy.
I see now in the update that the Signing secret is optional I left it blank. I will continue monitoring the issue for the next few days.

Thanks again!