After 45 minutes in the Ocean, my watch will not accept a charge or turn back on
After 145 minute swim in the ocean might watch, asked to be charged, but now it’s just dark with a tiny green charging arrow
Question marked as
Directly from Apple
"If you have Apple Watch Ultra, you can wear it during recreational scuba diving up to 40 metres (130 feet) and other activities such as swimming, showering and water skiing.
Apple Watch Series 2 and later can be used for shallow-water activities like swimming in a pool or ocean, but you shouldn't use models other than Apple Watch Ultra for diving, water skiing, or other activities involving submersion below shallow depth or high-velocity water.
Apple Watch Series 1 and Apple Watch (1st generation) are splash- and water-resistant, but submerging these models isn't recommended."
You may need to take your watch to the Genius Bar to have it looked but it sounds like too may have gotten water in it if it's not reactive.