Apache Server Not Accessable Outside Network

So I have setup a Apache server to run a small website of mine. On my local network it works fine, being that I have setup the computer as a DMZ and so I simply input its static IP that I have assigned it and the website opens. I then continued to use the asuscomm DDNS to set a DDNS for my network so that I can access the website using the now created URL/DDNS; and as I presume most of you have guess the link works fine, on the local network. I can ping it, get a reply, and I can access the website it self, but once I go outside the network I can not either ping or see the website and its pages. No my ISP does not block port 80 and I believe that I have set up the DMZ correctly, and yes I have tried port forwarding to no avail. Any ideas would be greatly appreciated being that my colleague/partner has already given up on the project and thus I am left to fix it by my self.
Any help is greatly appreciated.
I hope you have a nice day.

Can you access it outside the network using your WAN IP?

No, inside of the network I am able to but outside the network I am not able to

what are you using to access it "outside the network"? like 4g cell? home wifi?

I have tried it on a physically different network on a different network in a different location, and I have tried it using a VPN, more specifically PIA

Have set up the port fowards as well?

I have and it didn't work either

When you access it from external, have you attempted to use the external IP address?

Yes, yes I have

how about taking it out of the DMZ and just forwarding port 80 to the apache server?

Tried it as well, nothing changed...

are you able to do other ports like can you forward ssh to the server and access that externally? (don't leave ssh forwarded except for this short time during testing without hardening your ssh if you don't already know this)

So, are you sugessting to forward ssh to the server and then trying to access the server?

Some ISPs (especially in America) are not happy with self hosting unless it is on a business connection. Some go as far to block incoming requests to certain ports to ip's regardless of ports being forwarded.

I would try opening a different port (say 25565 for example) and internally redirect it to port 80 and see if it works accessing it that way.

I am just seeing if any forwarded services will work, doesn't have to be ssh could be ftp or some other service.

If it all works internally there is a issue with ether the ISP blocking it, or the router is not really forwarding the ports or is forwarding it to the wrong place. Or you have something setup wrong

when you tried different ports did you change the url to reflect that new ports?

ie mywebsite.com:randomport

For one we have tried different ports already, but nevertheless our ISP does not block port 80, at least that's what we found using websites such as can you see me.

it shouldn't be too terrible to set up.

on the router, you forward port 80 to the apaches address like 192.168.1.25.
on the server make sure it allows 80 in.
that's pretty much it.

type in the external ip or ddns.

That is pretty much exactly what we did but still external clients could not access the server

Yes, when the ports where changed I changed the URL to accommodate.

and if you use the external ip/DDNs it works when doing it internal? assuming i read the op correctly that is a yes. in which case the isp is most likely blocking you

when you do a ping DDNS what IP does it return, when on local?

what about when you do a ping DDNS what IP does it return, when on remote network?