@David4351
It was in April and now is July. I am afraid now is too late.
You should have to contact your host, explain the problem and give him a chance to fix it within 24 hours.
If it wasn't fixable then you should have to contact Airbnb to cancel your stay, refund you and relocate you (or you could find another place to stay)
The host will never cancel on his behalf because he would be penalized. And he didn't ask you to leave, it was your decision and you wanted a refund so you should have followed the procedure to get it.
This way, you didn't cancel, you kept his calendar blocked and he wasn't able to rebook those days and that's why he is refusing to refund you.