Transactional Replication Synchronization taking too long to respond
Check the following things please:


Snapshot Agent shows as completed successfully and it has generated its files
Log reader agent is running and delivering


Right click on each service -> view details - that will help you get more info.


To add to the comments, check the subscription details:

Go to each tab and see if there's any error. If all is good, they should all show green, running, with an action list of delivering transactions.