You've likely been observing client-side caching.
DNS records come with a best-before date of sorts, the TTL (time to live).
A client may rightfully cache a successfully resolved domain until its TTL expires, and thus may have had no reason to request DNS resolution again.
I'm also quite confident that Oisd is responsible here, as I have no difficulties accessing the sites you mention (and I am not using that list), regardless of whether I use unbound or my router or a public DNS server as my upstream.
You could consider to whitelist the respective domains blocked by Oisd, where the following post may help: