The signal to my house is just half of one bar on the reveption scale. I use wifi calling to make calls but even then get cut off. Making or using messages is spasmodic and cant be relied upon. Tradesmen working in my home complain of the same faults. My wifes phone is exactly the same.
O2 with all of its technology cant find a fault, but they have not been on site.
If I walk 20yards drom my door i can get two bars signal.
In concluson inside reception is unsatisfactory, outside is little better.
Try switching to 2g when indoors.
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