Are you saying that calls fail in different ways? Is this problem intermittent?
Assuming that if you call in from your mobile phone you see a problem, look at the Asterisk log to see whether the caller number and/or name are shown and whether they are presented to the called device.
For further details, at the Asterisk command prompt type
pjsip set logger on
sip set debug on
according to trunk and extension type. This will cause SIP traces to appear in the Asterisk log, along with the regular entries. Call in from your mobile. If the incoming INVITE from Flowroute doesn’t show the proper name and/or number, you should contact their support with the new evidence.
If the caller info is ok coming in but not being presented to the extension, the Asterisk log should show where it is getting lost. If it’s being sent to the extension but the phone is not showing it, the phone could be misconfigured.
In addition to the From header, other headers such as Remote-Party-ID and P-Asserted-Identity can carry caller ID info. If these are present but not consistent, there are settings in the trunk, extension and device that control which of these are sent and/or displayed.
If you still have trouble, paste the log of a failing call at pastebin.freepbx.org and post the link here.