LG G7 Thinq Bootloop + No Connectivity

Hello. I have an LG G7 Thinq that i have been very happy with for the past 3 years. The other night a combination of severe issues started:

• refuses to connect to both wifi and cellular networks. When i go into settings, the phone has no MAC or IMEI numbers.
• will not run for more than a minute or two before freezing and rebooting. I did get it to run for over 20 minutes straight once while running the LG backup app. Setting the phone on an ice pack seemed to help.

I have tried everything to fix this issue, including a full factory reset. I am wondering if this may be some kind of hardware failure? The only thing i can think of is i took it to the beach last weekend. I did briefly run the phone under a very light trickle of water to remove sand from the screen without scratching it. The phone is supposed to be waterproof though and it ran for over 3 days totally fine after i did that. Does anyone have any repair ideas?