Make dial plan

[Truong]

1. Brekeke Product Name and Version: 3.9.5.8

2. Java version: 1.8.0_251

3. OS type and the version: Window 10

4. UA (phone), gateway or other hardware/software involved: PhonerLite.

5. Your problem:I have:
- group extension 100: include 101,102,103
- group extension 200: include 201, 202, 203
- extension 500
Request:
+ From extension 500 can call to all other extension.
+ From all other extension can call to extension 500.
+ Between other extension can not call directly together (must via extension 500). ex: 101 want to call 102 (or 101 want to call 201) . the first it must call to 500 and then 500 will forward the call to destination extension.
I did try some dial plan but can not. Who have any idear make dial plan for this request, please support me.

Thank you!

[Harold]

> Between other extension can not call directly together

so what do you want if 101 calls 102 directly. the PBX should play any voice guidances?