@Sam Singh Does your request have any query(q) parameters? I don't see any in the above URI. The original image and thumbnail images are returned only if the news article has an image, if there is no image and if the 'originalimg' parameter is not set the URI for thumbnail and image will be the same. Please try something like this query:
https://resourcename.cognitiveservices.azure.com/bing/v7.0/news/search?q=corona&count=10&offset=0&mkt=en-us&safeSearch=Moderate&originalImg=true
The result contains the following:
"image": {
"contentUrl": "https:\/\/images.axios.com\/IQ6azjlzVLDggvrPfwJP1CXVFwo=\/fit-in\/1366x1366\/2020\/07\/28\/1595975863692.png",
"thumbnail": {
"contentUrl": "https:\/\/www.bing.com\/th?id=ON.EA6C8D548851AA26864C8CCADEB21FB8&pid=News",
Please check this image/thumbnail.
Image:
https://images.axios.com/IQ6azjlzVLDggvrPfwJP1CXVFwo=/fit-in/1366x1366/2020/07/28/1595975863692.png
Thumbnail:
https://www.bing.com/th?id=ON.EA6C8D548851AA26864C8CCADEB21FB8&pid=News
I hope this clarifies.