Nice ^^, a new problem.
And you have that after a restart too ? It make 50 requests, more than 1 by second, it make lot of request to check if a device is here.
Can you take a look in the database (with a sql editor) to check if it s not an old device badly deleted ?
The easy way, and sure at 100% you don’t break something, just make a backup using phoscon, inside the file (it’s a zip archive), you will find 2 text file and a sql one.