Moved server to new VPS

So….. bit of a brain dump here in general, looking for some advice on where i went wrong:

My VPS provider changed their operation so i can no longer mount a custom ISO to install, i have a new server needing set up so i figured I’d move to another provider that still allows custom ISOs.

Installing new server from latest stable freepbx 16, once installed/activated, module updates come. Break most things like userman etc so following the prompts on screen i install userman, sysman i think was one and also voicemail was complained about. I think that’s happened with every install i’ve done for quite a while now so i’m used to that.

Seemed to be working fine after that so i restored backup from old server and pointed the phones (P315) in sangoma portal to the new deployment. Turns out the new provider doesn’t have a firewall in front of the VPS so it’s was just fail2ban etc fending off the bots. System started crying and genuine phones were experiencing a bad time. System is only 2 cores, 4GB ram and 120GB ssd.

I went through config everywhere i could think of to update IP address/hostname etc and waited out DNS renewal times until things were apparently working, although i did have to reset the username for asterisk as the config had installed a hashed name instead of plain text so it failed when reading.
I realised at some point that dpma had errors, when i went to management it only said “License not activated” I ended up switching dpma off and on again and that reinstalled it which got the redirect from the portal working again. With the constant spamming going on to port 5060 i figured I’d be clever and change the SIP port in asterisk SIP settings to 7000 (not sure if this is anything more than a drop in the ocean compared to firewall but that’s all I had at the time). Restarted and broke all connections. I changed the DPMA port to 7000 as well but nothing would connect. I feel like sangoma P315 using Zero touch/sangoma redirect can only use 5060 but would love it if someone could confirm?

Currently i’m back on 5060, phones are working again but system being hammered by bots as you would suspect. I have 2 other systems the same but they are using yealink phones through normal SIP connections and are quite happy using port 7000, I am yet to see if the port change will actually make any beneficial difference though.

I’m not very experience as you’ll have guessed a few sentences in and wondering if someone could comment on my story pointing out the vastly stupid things I have done and offer advice on what to do instead? Are the little quirks i’ve mentioned just part of it or are the signs that’ i’m going badly wrong from the off?