Your Samsung Galaxy S8+ has the IP68 rating which means it’s dust- and water-resistant. However, it doesn’t mean that the phone is already invulnerable to water. Being resistant to water doesn’t mean being waterproof, so if you recently used your phone to snap photos underwater and then you’re being warned about moisture in the charging
moisture detected warning
The moisture detected error in your Samsung Galaxy A5 is actually a warning so that you won’t charge your phone because it’s probably got in contact with any form of liquid and as we all know, water and electricity don’t mix well. At least, that’s the most common scenario if you’re getting warned like this.