When you’re dealing with a text that changes you can’t use that text in the selector and expect it will match the next time.
When you’re dealing with web pages on mobile, you can leverage the UiAutomation tools because ultimately the engine used underneath for web sites is the same. So you can open the site in a normal browser and use UI Explorer to inspect all properties and find a simple, stable selector (for UI Explorer to appear in toolbar you have to install UiPath.UiAutomation.Activities ~ temporarily if you don’t need it otherwise ~).
MDM tries to get a good selector but it’s not a replacement for what a human can do. If you craft the selector in UI Explorer you can use tag, class, parentid etc to uniquely identify the element containing that text, without actually relying on the text.
Hope this helps!