Hangfire creating suspended SQL server threads

Hi All,

Our application is using Hangfire to handle incoming messages towards our backend DB/Application.
Hangfire is using SQL Server Standard 2019 and has 50 workers on one server.
We handle ~1500 messages per hour. We face the below issue :
1.When a batch of 1500 messages arrive, we see ~250 threads in our SQL server.
2.Message handling jobs are completed
3.When the next batch of 1500 messages arrive, we see a number of ~250 NEW threads in our SQL server. This contintues to happen until our SQL server is going into thread starvation.

I am not the dev of our application. Any hints here why hangfire keeps creating new threads while others just stay in Suspended state? They are released ~1.5 hour after they are created.
SQLserver_hangfire