New Sim has half strength signal

[MikeH14]

Before I contact O2 I thought I’d come here first to see if there’s anything I could try first. 

I upgraded my contract last week, as a result of which O2 sent me a new sim for my handset (iPhone 13). 

On my previous SIM card I had full signal (4G) all the time. The nearest cell tower to me is clearly visible from my bedroom window, just a stone’s throw away. 

Since getting the new sim I’m only getting half strength signal (4G).  

I guess it could be coincidence and perhaps the tower near me is undergoing maintenance. 

Any suggestions of what I can try to get a full signal once again before I call O2? 

I have tried rebooting my handset. 

Many thanks. 

[MI5 · Accepted solution]

@MikeH14 

Check here first O2 Service Status

Guide: How can I sort out my network issues? 

[Bambino]

@MikeH14 There's this guide as well: Why do I have poor coverage indoors? (o2.co.uk)

[MikeH14]

Turns out that the transmitter near me is undergoing maintenance.  I'm guessing it's on "low power mode".  Many thanks for your help.

[MI5]

You’re welcome @MikeH14