How do I remove water lock in my phone

There is no actual water lock . The phone is just water damaged. You can tear the phone apart and clean it and hope for some results Vue éclatée du OnePlus 5

Clean every connection with a soft toothbrush. As well clean the logic board; use a 99% isopropyl alcohol for all cleaning. Now is the time to start drying out the phone. Set the screen in a desiccant or silica gel leave it in for several days moving it from time to time to get the max effect from the desiccant. Use a blow dryer on a low heat setting to dry the rest of the phone. Only use a hair dryer once you have cleaned the phone completely with the alcohol. Do not attempt to dry the phone if it’s still wet with water with the blow dryer as this only spreads the water. Replace the battery with a new one considers the old ones done. Clean again with isopropyl alcohol let dry and when you think everything is clean and dry reassemble the phone (make sure to clean the contacts on the screen after removing from the desiccant). Once you've reassembled the phone it’s time to power it on. Hold your breath and hope for the best

One last thing the motherboard is sealed and should be water resistant but the connectors are not so concentrate on the connectors . if the home button fingerprint scanner wont function and the phone powers on then the only real fix is to replace the display assembly as this is a complete unit Hope this helps