Keep an eye on the influence level on your planets: the information is visually displayed around the planet on the zoomed-out GC view and also in the summary top left of the screen when a planet is selected. For details about the new influence and resources systems in TR nowadays can look at the documentation guides in-game (icons down the left hand side of the screen in GC mode). Here's a few extracts to summarise:
Influence
Having Low Influence level (1-3) on planet can cause Unrest. High Influence (6+) removes Unrest. After getting 3rd Unrest Stack planet will Revolt one week later. All forces currently located on that planet will retreat to another planet. Control of that planet will flip to their preferred faction.
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A planet has revolted because of low influence. Influence is tracked in the top left of the screen, or in the bar to the left of planets. A red fist indicates unrest exists on the planet, and after a week with 3 unrest, planets will leave your faction. Doing things to increase influence, like making sure you have proper resources, building companies, and various other things listed in the guides accessible by pressing the buttons at the left of the screen above the minimap can help prevent this. You can also blockade enemy planets if they aren't producing food to give enemies unrest.
Resources
There are two types of resources in EaWX - SPENDABLE and ROLLING. Spendable resources include CREDITS and SHIP CREWS which are used primarily to contruct ships. ROLLING resources (FOOD, INDUSTRIAL PARTS) are not spent directly, and instead costs and expenses for each are determined per week, resulting in increased or decreased levels of planetary influence, or other effects depending on the resource.