I had the same issue and I finally found that the solution is to purge the previously deleted resources. In my case, I searched for "Language Service" in the search bar and then clicked over the "Manage deleted resources". Then I selected all and clicked "Purge. Hope this helps!
Not getting Free Tier option to choose despite all resources deleted in the resource group
DUSHYANT SAPRE
5
Reputation points
I am seeing the following message when I am creating a language resource under the default resource group: "The free tier (F0) for this resource type is already being used by your subscription, therefore it will not appear in the dropdown below.". I have deleted all the resources under the "only" resource group I have.