Getting troubled with the battery of galaxy s9+ now seems a common problem. Buying a premium flagship smartphone from such a reputed brand and getting as low as 2hs of screen on time does not make any sense. Going through online articles just gives a bogus answers. Why would anyone pay such high price and stop using basic features instead we bought this device to use 2k display on it with all the features you provide turning on. Turning off wifi or turning on airplane mode, are you serious samsung!!?? Is that all you got in the name of "solution" and nothing new even that doesn't work. It's your so called flagship smartphone and your customers all over the world are trynna find some solution to this irritating battery life of your device. Please take this as a request to get "a working solution" from you, from all your customers facing this issue.
Try and Clean your phones storage sadly i am not familiar with thr S9 but if it has the Device Care option on settings try and clean your memory or storage that may be a solution or stop background apps which can consume battery life quickly if nlne of these solutions helps then it may be the battery itself now remember im no phone expert these are just helpful tips and assumptions hope all goes well!! If somethings wrong just ask!