importing excel into planner

I am experiencing the same thing.  Power Automate states Successful, but the card never shows up in Planner Premium.  I have read else that the issue may be due to a Private Channel restriction, but this shouldn't be the case as this how businesses build the security between functions and maintain the "Data Privacy" requirements.  Why does the tool have this limitation if Power Automate is the only avenue to import into Planner.   And for what unknown reason does Microsoft continue to ignore that its project planning tools should be able to import from Excel, just like any other project tool on the market.  -- Excel is own by Microsoft.....it should be easy to accomplish and is 5 + years in the making.