Updated: August.5.2018This is still an on-going issue, please see the suggested troubleshooting tips:
1. Rearrange your kitchen to make sure nothing is blocking the stove, fridge, sink etc.
(Example: a window in front/side of the fridge. = If it opens into the window's space. That may cause problems)
Also, put up the walls to see if there's any cabinets, vents or decor items that maybe too large and/or blocking the Sims from cooking or getting to the stove, microwave and/or fridge. - It's been reported removing the obstructing item helps. For example, if you put the pots and pans decor above the stove and it hangs down to far, your Sims won't be able to cook.
2. Delete the fridge and/or stove and replace them with less expensive or better appliances.
3. Outdated Mods/CC are known to cause this issue. Best way to test if mods are the problem is:
Move your mods folder to the desktop, clear the game cache and delete the localthumbcache.package from the Sims 4 folder to help make sure there isn't any issues with mods. Like mods/cc that are outdated or no longer in game.
How-To: Fix Problems with Mods/CC
http://www.carls-sims-4-guide.com/forum/index.php?topic=25031.msg426156#msg4261564. Turn on cheats, 'testingcheats true' then right-click on the fridge and click 'debug'. Turn off cheat after you are finished.
5. The house itself may be bugged. Save household to library. Place a different house on lot, and move household back in.
6. Repair Game:
In Origin > Games Library, right-click on Sims 4 and select Repair. - Do note this repairs the game's install files for the actual game. It does not make any changes to the saved game files. Meaning that your saved games are safe, they won't be deleted.
7. Start a new game for testing purposes to see if the same issue pops up. This helps determine if it's something in the older save or not.
If you've tried everything above and nothing is working, please consider creating a report about it at EA AHQ Sims 4 Bug Report Forum -
https://answers.ea.com/t5/Bug-Reports/bd-p/The-Sims-4-Bugs
Delete Game Cache Files (What and How-To)
http://www.carls-sims-4-guide.com/forum/index.php?topic=29288.msg401662#msg401662