why isn't number showing?

[terrie80]

Both sims are currently with smarty
Under settings/about phone/
slot 1 shows the phone number
slot 2 says unknown.

[MSF]

@terrie80  You don't say what phone you are talking about here.

Have you checked on your account dashboard to see that both SIM cards are active?

If it's a phone issue, then you may get more information on a forum for that brand.

[terrie80]

It's a Fairphone 4.

yes, both are active. 

[MSF]

@terrie80 Well, if both sims are definitely activated and only one is showing in a two sim slot phone, then do you think it's a phone problem?

Have you looked at: https://support.fairphone.com/hc/en-us/articles/115001041206-Find-fix-an-issue-yourself ?