I called back number (02) 8599 0118 reached IVR for a company called Telecom.

If the they every day, at the same time.
Or call more than once a day.
Don't leave messages.
And when you call back you can't get through to someone.
It's a call centre, telemarketing.
Just block the number, if it's important they will leave a message and be easily reachable.
These are hallmarks that someone got your number on a list so be prepared this won't be the last.

to many calls

telemarketer rang it back and an automated voice says you hav
e called Telecom .