Hi mayanklohani,
Try with following code, works fine with me:
#flexContainer {
display: flex;
-ms-flex-flow: row nowrap;
}
I do not have images for test, I use some div box instead, but I believe they should be same.
If I do not add display:flex, the result as below:

After the display: flex has been applied, the result:

--James
<THE CONTENT IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND, WHETHER EXPRESS OR IMPLIED>
Thanks
MSDN Community Support
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