ASM Event Log Requests

Hi, I'm Using Bigip ASM Ver 13.1.0.6. I Have a problem with the ASM requests log, it getting too large over 4 milion requesst and we can't search anything in it, every search lead to a system error that says: "Failed to Load Request", when i try to delete all logs from the WEBUI it failed and let me delete only 10000 request each time... i know that the logs stores in the db and i wondered if there is any workaround to clean all the request log directly from the db or if there is any other way to clean them up. thx.