If pendant is used to describe past durations with a clear beginning and end, and the imperfect is used to describe continuing actions or habits in the past, why is the example "J'étais là pendant quarante-cinq minutes" instead of "J'ai été là pendant quarante-cinq minutes" since the passé composé is used to describe actions with a clear beginning & end in the past.
Is there a rule exception for using pendant and l'imparfait?