Exception when accepting a request if [current time] > [requested publish time]

1. Log-in to CMS as author
2. Create a new document
3. Send a scheduled publication request
4. Log-in to CMS as editor
5. Navigate to above requested document
6. Wait for the scheduled publication request time to pass plus two minutes
7. Now accept the request

Issue - I see below exception (refer screen-shot)

No context defined for class java.lang.String