Nokia India — nokia 6.1 plus (blue, 64 gb)

Address:

275/3, Devi Pura IInd, Bulandshahr, Uttar Pradesh, 203001

Dear nokia team,
My sister ordered this phone last year on 20/09/2018 for my mother. It was working fine but she has been facing a issue that is her phone does not ring at all. The sound on videos and everything is fine but ringing tone is not there. We have checked the settings many times. Have taken help of mobile shop people but we are not able to figure it out.
She has been facing this trouble from last couple of months.
As she lives in bulandshahr, up (203001) and the only service centre in that area has been shut down so we dont know what to do and where to complaint.
We tried complaining on phone too but that dint help.
We are very much in trouble due to this.
Please help us for the same.
I am attaching the original invoice.
Warm regards
Urvashi raj