@John4972
I am afraid this is a bit complicated as Airbnb has changed its COVID refund policy a few times over the past few months. When you cancelled, what options were you given? Did you specifically cancel giving the reason as COVID? Did your host have to authorise the refund? I know that for some time, guests were prompted to accept a travel credit if they wanted a full refund. There has been a lot of debate on this forum about it so you could do a search here for more info.
As for the credit not appearing in your account, you might need to 'activate' it. This happened with my Superhost travel credit. It did not appear in my account and then Airbnb told me that's because I never activated it from the link in the email I was sent about it. Maybe check the email you got when you cancelled to see if there is a link.
Also, if you received credit and used some of it, the remaining credit does not automatically appear in your account. You have to contact Airbnb to get it activated.
I doubt if the credit is there for as long as you want. From what I understood, it was valid for one year only.
