Sudhakar,
It seems you are using the 'Require Oauth 2.0 Toekn' Policy Fragment instead of the assertion which is causing this. The reason you are getting the below error:
missing or invalid context variable : catch_lifetime
is because that context variable is not being set in the Policy Fragment. You will need to use the 'OTK Require OAuth 2.0 Token' assertion itself for this. Once applied to Policy, a window will pop up where you can set the value.
I hope this helps.
-Alec Daniello
APIM Support