Great question!
You can use ‘been’ with the -ing tag on the verb in most cases and this is called ‘the present perfect continuous’ or ‘the present perfect progressive’. The only times you cannot use this is when you are using a stative verb. Your verb ‘work’ is not stative so it can be used in both the present perfect simple and the present perfect continuous.
“I have worked at ____ company for 5 years.” (correct)
“I have been working at ____ company for 5 years.” (correct)
However, if you are using a stative verb like ‘know’, you cannot use it in continuous tenses.
“I have known her for 3 months.” (correct)
“I have been knowing her for 3 months.” (incorrect)
Stative verbs usually relate to thoughts, emotions, relationships, senses, states of being and measurements. I would suggest that you research them so you know which ones don’t work in the present perfect continuous tense (have been verb+ing).