Unable to verify step on Create a Data Stream unit

Getting the following error when clicking Verify Step on the challenge, despite having created the field as required. I did accidentally create the field label as "Is Us Based." (with the fullstop) but the API name appears to still be as required. I got an error when trying to edit it, then I disabled the field to try and re-create but now I can't re-enable it.

We can't find the field ‘Is US Based’ (API Name includes ‘Is_US_Based__c’) associated with the Data Stream ‘Lead’.

#Trailhead Challenges