This is the reason I recommend Smokes Powders since they have been tested by so many and the work with the shake & bake.
All powders will spray and that is the clients Eastwood services, but all powders will not tumble coat.
Over the years I have done a lot of business with Prismatic Powders, Prismatic is a manufacturer, and have had good luck with then. So far all the Prismatic high gloss solid color powders I have tried have worked with the tumble method. If you venture away from those I would recommend you invest in a powder gun.
To salvage what you have I would suggest doing a pre-heat on your bullets, but you must have an accurate thermometer like the glass Taylor Oven Guide to monitor the temperature. Heat your bullets to 140 degrees then do the shake, keeping them constantly moving until coated. If you overheat or don't keep the bullets moving you can end up with a ball of bullets. I personally use pre-heating as standard practice as I am in the high humidity Gulf Coast, but I am also dropping the bullets into my just for bullets homemade tumbler. Good luck.