1. You have to go to your router configuration webpage, mines 192.168.1.1 on my internet browser.
2. You have to look for your wireless advanced settings, we're looking for this settings:
Here's the trick, if your router is affected and is causing you wakelocks, default value of Beacon Interval will be 100, and DTIM Interval will be something like 1.
DTIM interval is how many intervals the router buffers data, so that devices in sleep mode will wake up and catch the information. Default on many affected routers is 1, meaning that the phone wakes up for every bacon, or 10 times per second.
Beacon Interval should be reduced to 50. This may seem counterintuitive, but your phone, if it mistimes waking for a beacon, will stay awake until the next beacon. This cuts that wake time in half, thus conserving battery.
3. Change the value of DTIM interval to "30", and Beacon interval to "50".
4. Reboot your router.
You should notice improved battery life, I also revoked auth permissions of Google Search app for keeping the phone awake and location, you guys could try that too.
Hope this helps, please let me know if this worked for you guys