I might be wrong but I think you posted another question a couple of days ago that started "After that the ..." followed by something which happened in the past. I think you are having a problem with this construction. If you start with "After" and follow it with something that happened in the past, then "that" is not appropriate.
After the promise about the pay rise wasn't/hadn't been kept, the staff went on strike.
Note that we don't use "struck" as the past tense of "strike" when it means "to stop working as a protest".
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