The syntax of the URL is invalid. There are three ways to use this service
Country List
Add a list of ISO3116 alpha-3 country codes to the URL. For example:
https://covidapi.pnhosting.net/GBR,USA
This will return all data for the selected countries for all dates.
Country list and start date
Add a list of countries as per above, but also add a start date in the format yyyy-mm-dd. For example
https://covidapi.pnhosting.net/GBR/2023-01-01
This will return all data for the selected countries that are after the specified start date
Country list, with start and end date
Add a list of countries and start date as per above, but also add an end date in the format yyyy-mm-dd. For example
https://covidapi.pnhosting.net/GBR/2023-01-01/2023-12-31
This will return all data for the selected countries that are between the specified dates