Overflow of unexplained calls

[DjeSan]

Hello, I hope you are well
so, I've been having problems recently, the reception number receives calls from our call center, basically calls coming from outside, but the number to reach our company is another number, I'd like to know why the incoming calls overflow onto the reception number I'm at your disposal if you need any further information
we are on ox 4400 R10

[DjeSan]

Basically, I'd like to know which parameter shows that call forwarding has been assigned to a particular number.
calls come from an entity