Hello... I am also a spidigo user, and I have also faced same problems. Here are few suggestions.
1) Call frequently to spidigo @ 079-66199999
2) If they don't answer properly, be aggrasive on them. Directly go to their office and have guts to fight with them. Going to office worked for me. Since 6 months I have not encountered any problem.
3) Now something technical... The device installed on terrace may not be in right direction, like it was installed. Try moving it and check whether you get full network strenght or not. You can observe this by the small led lights behind the bullet or TP-Link device, mostly in green color.
4) regarding to the busy tone on complain number, yes it is true. But by trying again and again it will connect to the customer care. Once you talk to them, make sure you ask for trouble ticket (complain number).