What version of FMGo is on the device you are having problems with? You may need to update to the newest version.
What ios version? This may need to also be update
Are the ios version and FMGo version different from your device? verify that the user has the same version as your test device that doesn't have the issue.
Make sure that the tab control is contain all in one body part. You may want to shrink the tab control and then test.
Thanks did all the above and made corrections. I have also added a simple: leave layout and return to layout button, as an attempt to refresh the the tabs. I have not been able to recreate this issue, so lets hope this solves it.
Thank you for the help.