@Ihor Dyrman , Kindly review the Jobs and logs to isolate the issue further:
For continuous WebJobs - Console.Out and Console.Error are routed to the "application logs", they will show up as file or blob depends on your configuration of the application logs (similar to your WebApp).
Kindly check this document for more details - https://github.com/projectkudu/kudu/wiki/WebJobs#logging
I have seen cases, where having unnecessary app settings on the configuration blade of WebJobs on the portal caused reboots.
Kindly identify and remove unnecessary app settings as required (as a test).
Also, kindly see if this setting is present ‘WEBJOBS_RESTART_TIME
‘-Timeout in seconds between when a continuous job's process goes down (for any reason) and the time we re-launch it again (Only for continuous jobs).
Could you please share more information of your WebJob and Webapp? What App Service Plan are you using?
P.S. Kindly do not share any PII data on the public forum.