Jobs in Running state for too long

Hello everyone,

We have some workflows built in our environment. Few are event triggered, some are timer triggered and rest are for manual run by the analysts when required. Now we have been facing the this issue of workflow jobs get stuck in Running state for like more than hour/hours and moves to failed state after timeout. What is the reason behind this? All these workflows were working fine until 3 to 4 days back.

Thank you!