Ionic 4 tabs navigation to root page problen

Hi I’m programming an Ionic 4 app and I have a problem:
If I place a button in one of the tabs pages !!!THAT ISN’T THE ROOT PAGE!!!, which leads to another page it work fine. But if I go back to the tabs pages with an ion-back-button I’m sent to the root tabs page and not to the page I was before.
Can anybody help?