With them and with him

Hi Torston
Please, can you tell me why we don,t use (with him or her) instead of (with them)?

(If you want to see a lawyer, you make an appiontment with them)

Here “lawyer” is a singular noun,and the pronoun that represents singular noun usually singular too acording to my limited information about grammar.

Lawyer = him,her.
Lawyers = them.

I found these kinds of sentences in many books, and this matter often confuses me a lot. Of course, there is a rule that explain why we use this.
Best wishes,

I agreed with you, the correct ones should be
If you want to see a lawyer, you make an appiontment with him or her.
If you want to see lawyers, you make an appiontment with them.

In English, I saw some unusual subject-Verb Agreement like :
Someone calls you, don’t they ?
Someone is coming, aren’t they ?

Even they are incorrect in grammar but people usually use it in daily speaking.

You appear to be speaking about the so called ‘singular they’, which has become widely accepted as a third person non-gender specific singular pronoun (where it is not known whether the person is male or female).

Hello Beeesneees.
Thank you very much.
You are always ready to answer us.
Now everything is quite clear. Iam not confused anymore,
after explaning the (singular they) non-gender specific sigular prounoun.

Best wishes .

Hi Waiyin.
Nice to meet you.
I have never come across such tag question.
thanks for this information.
I like strange things . They make me feel excited.

(Someone calls you, don’t they?)
(Someone is coming, aren’t they?)
This is really fantastic.
best wishes.