@David-TP 

Thanks for that info.  I realised that I could edit the profile, but that made no difference as the current profile was correct except for the authentification which was set to CHAP.  Setting to PAP offered no help so I reverted to the original.

The SIM worked just as badly in a mobile phone, and having restarted the X50 on numerous occasions the download speed has not improved. 

Its also true that the speed improves for short periods and I wonder if (given that EE) are the only ones offering 5G here) the mast is being loaded up a lot.

Its sad that it was really good (150Mbps+) for four months , now its no better than 4g and worse than FTTC.

Given all the hype surrounding 5G (low latency - hah) I feel I've wasted my time at present and will need to reinstate the copper cable.

Many thanks again

  @Gort   @Gort do you have the EE APN settings I could use?  

I've been using a different router for 2 years on EE until recently (coinciding with a mast upgrade near my flat).  My internet speeds were beyond terrible for the 2 weeks of the mast work and also when the work was completed.  It was only after I demanded a replacement SIM that they improved.

I'm trying to set up an X50-5G tonight but it doesn't like my APN settings (and saying the Sim isn't working).  Any tips appreciated!

  @Gort thanks for the info.  I think CHAP is the only authentication type I haven't yet tried, but I'll give that a shot.  Nothing else has worked so far.  TP-Link advised me to use PAP so I've stuck to that for now.  
 

it turns out I was a couple of firmware versions out on the router, so I've updated that too.  If CHAP doesn't fix it I think I'll send it back and wait for the WiFi 7 version to come out.  Hopefully it's less buggy than this model! 🤬

My local cell site has just been updated by the way but my current router is working fine since their updates.  My 5g speed has quadrupled too, so I don't think it's the cell to blame.  
 

I've only managed to get the SIM to 'click' in one direction so far, so I think that's ok too.  The system logs identify it as 'ready', which is encouraging too! 

  @Gort no joy with those settings for me unfortunately.  They're the same settings which work fine on my Huawei router.  

My TP router seems intent on flipping between the 'no sim inserted' error and the other claiming my APN settings are wrong.  
 

I test software for a living so I think I've tried every possible combination of settings now in as clinical a way as possible.  I'm still highly suspicious that they shipped a product with known bugs relating to internet connectivity 🤷‍♂️

  @Leeds_guy 

Maybe the router is  actually faulty.  Which is a shame as I haven't had any big issues with the box itself once I got over the speed problem.  Its been running fine overall for 6 months.  Good luck with what you decide. 

  @Gort 

I am having a similar issue with an EE sim card in a Deco 5G router.  I have used the X50-5G for about 7 months and now all of a sudden, it has stopped working.  Either the Deco can't find the SIM card or when I do manage to get it recognised and connected, it runs for a few minutes and then the solid red light comes up.  I have tried rebooting it both with and without the sim card in it and have used the sim card in a mobile phone (which works fine).  Thinking that perhaps the Deco was broken, I bought a new Deco router - the X80-5G - but I am still getting the same problem.  Any suggestions would be gratefully appreciated please!

Thanks

Sharn 

  @SharnM  I couldn't get mine to work at all and based on some comments on here and Reddit relating to the product's reliability, I decided to return mine rather than go through the pain of constant tweaks and resets to maintain it's connection.   I hope you have more luck than me!

  @SharnM 

That doesn't sound good.  My units (I have 2) have been working fine since the slow down.  I'm worried that you have a second box which also doesn't work which seems to point to something else.  Ultimately my issue was the phone mast I believe.  I've only had one further problem when the internet went down.  A reboot fixed things so I'm not sure if it was the box or the mast.

This isnt helping your problem.  The main issue is that alternative 5G modems are frighteningly expensive, which makes no sense to me as 4G modems are cheap.  

I'm sticking with 5G at the moment as FTTP is also a ridiculous price