Former floor covering installer; it’s literally a 30 minute job, maybe less. The carpet has become stretched which does occur over time. The affected area just needs to be detached from the tackstrip, restretched a bit and reattached. I would recommend finding a local installer who does side jobs. If I were to take on a task such as this I’d charge about $50-$75. A person could peel up the carpet and just use a knee kicker but that will not stretch the carpet properly and the problem may reappear in a couple of years. Hope this helps.