Unknown Number — Missed calls

Address:

Thane, Maharashtra

I am receiving Missed calls from unknown numbers. When I try to call back, it restricts> It seems to be international number... This is the detail:

1 [protected] Missed call -11th sep - 20.47
2 [protected] I made call but it says I have to activate this facility - 11th sep - 21.58
3 [protected] - Missed call - 14th sep - 8.20
4 [protected] - I made call but it says I have to activate this facility - 14th sep - 8.21
5 [protected] - Missed call - 14th sep - 09.13
6 [protected] - I made call but it says I have to activate this facility - 14th sep - 09.38

Please look into the matter.