Setting up FreePBX (Asterisk) on Raspberry Pi (Binotel, Dinstar, USB-Dongle)

I am looking for a specialist to configure and resolve a number of issues with the telephony system that I set up based on Asterisk FreePBX 16.0.40.11 (Asterisk 16.21.1). Basic configuration has been completed, but there are several critical issues that need to be addressed.

Tasks:

1. Configuration of the SIP protocol, ports, codecs, NAT. For the proper operation of clients and the server with/without NAT.
2. A test USB-Dongle is connected, incoming calls work without problems (excellent call quality, call recording, email connected, SMS sent to email with call recordings).
3. There is a problem with outgoing calls — sometimes the client cannot be heard. This is resolved by redialing or several attempts.
4. Working hours, queues, and greetings have also been configured. Guidance on dialing rule templates is needed.
5. It is necessary to set up a connection to Binotel to receive calls from multi-channel numbers 0800... and 044..., as well as to make outgoing calls from the number 044.
6. It is necessary to configure the Dinstar GSM gateway with 4 SIM cards, which is currently working with Binotel.
7. Recommendation for an Android client to work with telephony (which will definitely work). It is also necessary to configure one test phone.
8. Clients within the network work with Asterisk within one LAN network, but there may also be clients behind NAT.
9. Analysis of settings, log files, and resolution of identified issues.

I look forward to proposals for the execution of the work, as well as estimates of time and cost.

The work will be carried out in Anydesk at agreed times.

Access:

• SSH Debian (Asterisk)
• WEB Admin FreePBX
• WEB Dinstar admin
• WEB Binotel (with rights to view credentials for internal lines)
• List of SIM (GSM) and Binotel numbers (0800, 044)
• Web TP-Link AX1500

If you need clarifications, please write.