Hi Ankit,
The feature is simply not called time skew but validity peroid. As written in the docs:
In addition, you specify a validity period in the sender agreement, within which the delivery of a message is accepted (based on the time stamp).
So you have to set the timestamp on one end (this is what you already did) and specify a permitted difference between timestamp and actual time the message was received.
Please see the part on 'Security Settings for Time Stamp and Expiry Date of Signature' in the docs.
Regards,
Patrick