Unable to accept diverted calls

[Edawsey83]

We have recently had an electronic gate installed, with an intercom, that uses a Vodafone sim to call our mobile phones when we have a visitor. 

The gate intercom calls my Giff Gaff (O2) mobile with no problem. It also calls my Vodafone work number with no problem. But it will not call my husband's Vodafone mobile number. Are there any settings that he needs to adjust to allow a call from a specific number? 

For reference; The intercom is currently set up to call my number first, then divert to my husband's number if I don't answer. But it simply won't. I have swapped the preferential order, so it calls him first and then me, but again it just won't call his number and calls mine. The gate manufacturers (Videx) have tried their own personal numbers, and the installer has tried his number, and it works fine, so it's definitely something to do with my husband's number. 

Help! Any suggestions?? Thanks! 

[AnnS]

I suspect this is connected to the number you have set up for your divert @Edawsey83 , although the gate calls your Vodafone number, it won't accept an additional option.

The divert is managed on the network and can only be set to one number at a time and you may have set to divert to your Giff Gaff number.  If you changed the divert to call your Husbands number first the call may not call your Vodafone number.

Your can cancel and change the divert here: How do I manage call diverts? but this will mean placing the SIM in a phone.  Although I have not checked, there may be a way to change the diverts through your online account.

If you are using a PAYG SIM  the only number the divert can be set to is voicemail.

[Edawsey83]

Thanks so much for your response. 

We have tried with several different phones and numbers. All work perfectly well. So for example, the intercom will call my Vodafone work phone, if I don't answer, I will call my giff gaff personal phone and vice versa. 

As soon as we put my husbands Vodafone number into the mix, even if we use his as the one and only number, with no other diverts, it doesn't work. 

Are there any settings from Vodafone that disallow diverted calls? 

[AnnS]

The only way to change the divert if on the link above @Edawsey83 if SIM is pay monthly and the divert is set to call only your Husband's number there is no reason for it not to work.

As far as is known you are only able to divert to voicemail from your Giff Gaff number.