The phrase "alert her that" is grammatically correct and can be used in written English.
It is typically used to indicate that someone is being informed or made aware of something. Here is an example of how it can be used: "Please alert her that the meeting has been rescheduled for next week."
Férnandez shook up the intelligence secretariat in December after it failed to alert her that Nisman was preparing to accuse the president of conspiring with Iran to cover up the bombing.
Maybe so, said the prosecutor, but why didn't Kamphefner send a letter, or a fax, or call her to alert her that Aerometals was using surplus parts and to get her permission?
We didn't want to alert her that we were there".
That pianist alerted her that "On Your Toes" was in the works.
Both messages alerted her that — once again — her information had been compromised.
Later, when Ms. Levine's friend alerted her that he was available, she would have none of it.
A relative alerted her that Metro Green was accepting applications, and Ms. DuPree-Nelson was approved for a one-bedroom corner unit at a far more manageable price, $1,200 a month.
She was waiting to go in for a mammogram, "trying to draw breath", when she started getting text messages from friends alerting her that Koch – in a prime display of protesting too much – was on TV tearing into her and Mamamia's "twisted agenda".
Each time, she will get a notification by email or on her phone alerting her that she just spent money at a merchant offering a Groupon Reward and how much more she needs to spend to unlock it: "You just spent $7 at Salem Coffee Beanery!
Unable to flush the migrants out of the reeds, she hiked back up the bank and into the modest riverfront neighborhood, passing a white dog on a chain who sometimes alerts her that migrants have arrived, unless his owner sets out food to distract him.
Taking your pit bull outdoors first thing in the morning, after meals and playtime, and before bedtime will allow your dog to adjust to a potty break schedule while alerting her that inside is not the appropriate place to eliminate.
