The currently Facebook update system every day, When you boost Page using Facebook & business manager(BM) Normal account your ads will run not smote, Example: Boost 100$ per day When Spend Boost 4k ADS Account will lost Threshold to 2$ automatic.
Solution : You need use Facebook personal ad account or business manager(BM) can spending money Boost 1500$ or Nolimit. When you use Account limit 1500$ or Nolimit Threshold will run smote 2$th to 900$ spending boost 4k to 6k and 90% not lost Threshold.
Note: You need use good Bank with Visa card don’t use Visa Spam, When use Visa card Spam your Ads Account will disable Ads.