"I need to tell her something."
Translation:Necesito decirle algo.
A number of these new sentences are missing a lot of possible translations.
As annoying as it is, this is what the report button is for.
It's not incorrect and should be accepted. However, the subject pronoun would normally be dropped in everyday speech because it's not necessary. I usually leave out the subject pronouns because it's less typing unless it's needed for clarity.
In this sentence "something" is the direct object; "her" is the indirect object.
So you need to use the indirect object pronoun, which is "le".
"la" is the female direct object pronoun.
I find the following webpage helpful in this regard: