Probably a grey area @thegodplato, but the iD terms & conditions state their network services are for personal use only. 

This iD online article might help though.

It is my personal phone, just also use it for work calls occassionally.  More worrying is the lack of mobile data at PR7 4AT area and, as for calls, the signal strength is also poor at home (some 30miles away).  Never had this with the previous providers.

Who was your previous provider, @thegodplato? 

UK mobile network operators have different infrastructure, and use different parts of the radio frequency spectrum that’s reserved for UK terrestrial mobile network operators. 

This means you can’t guarantee you’ll get the same signal strength at any given location in the UK with a different provider.

The OFCOM coverage checker is perhaps a little more realistic than those providers by the network operators.

https://checker.ofcom.org.uk/en-gb/mobile-coverage

Otherwise, try https://mastdata.com - they have real signal reception information for many locations in the UK, or another similar online service at https://www.opensignal.com. 

I have had both O2 and Vodafone and been able to use data whilst at my place of work and also no real issues for phone calls. It just doesn’t seem right.  I have been given a number to text to who I hope is some kind of ID tech support.

@thegodplato, maybe try the OFCOM coverage checker at your problem location/s for each network: EE, O2, Three and Vodafone. 

Which network/s seem best option? 

That OFCOM checker has outdoors as likely for all 4 providers.  Indoors is a bit iffy at my work address but I understand that.  Hence why most of us at work take mobile calls outside into the car park. 

Okay @thegodplato, sounds like whatever network operator is used at your workplace, the indoor coverage isn’t very good. 

Other than using the iD WiFi Calling service, not sure what to suggest - the network operators probably aren’t rushing to provide better indoor coverage in the area, sorry.

Thats Ok. Its more the outdoor one that I am not happy about which is meant to be OK and was with other providers.  Kind of defeats the object of having mobile data!

Thanks for the suggestions @andewhite, hopefully Wi-Fi calling helps out!

Why suddenly I have no phone signal in my house, what would be the cause? 

@Susan Bain - If it’s just calls that are impacted, it is likely due to the 3G Switch Off. Troubleshooting steps can be found here:

Thanks.

I have just returned from America where we used an E-Sim for data and had no trouble at all with signal even in the middle of nowhere.  Calls back home over WhatsApp some 4000miles away where perfect yet I still have issues making calls here in the Uk to people 30miles away.  The lack of any data when at work is also very poor and almost none existent so my question is why do I have pay for an inferior service.  Its really not great.  Phone is a Pixel 9 Pro XL so should be no issues with 4G calling, etc.

Some people have said I need a new sim?  Not sure why.  Only a couple of months into a 2 year contract, wished I’d stayed with previous provider now.

I have an iPhone 15 6 wks ago I suddenly can’t get a signal in my home, I had numerous live chats & tried everything they told me to do, no better, I was then told to go to curry’s for a new sim, 3 sims later & 3 visits later curry’s said they couldn’t help, back to live chat, one bar at my home & is also very poor in Clydebank where I live, was told to go back to them in a few days but curry’s told me it’s to do with them getting rid of 3G, it’s happening to a lot of people.  It’s very upsetting my mum is critically ill & I have no phone signal.  I’m so upset big companies always get away with it because they just fob you off.

Your signal readings between -116 and -136 dBm are indeed indicative of extremely poor cellular reception, where even voice calls become challenging. This level means the native signal is barely usable, but crucially, it’s often still sufficient for a properly configured mobile signal booster to capture and amplify. Unlike solutions reliant on broadband, a dedicated cellular repeater system utilizes an outdoor antenna to pull in this weak signal, an amplifier unit to boost its strength, and an indoor antenna to redistribute it throughout your space. When selecting a booster, pay close attention to its supported frequency bands (must match Three UK’s bands), maximum gain, and coverage area specifications. This ensures effective signal transformation from unreliable to robust. For a comprehensive selection of systems tailored to specific UK carrier bands and environments, exploring Myamplifiers.com would be a highly beneficial next step.

I feel your pain. Garbage network coverage. Can’t wait for my contract to end