Why is GP Petroleums falling/rising?

As of 17-Sep, GP Petroleums Ltd is experiencing a decline in its stock price, currently at 42.36, reflecting a decrease of 0.12 or 0.28%. The stock has underperformed its sector by 0.81% today and has seen a trend reversal after two consecutive days of gains. Over the past week, the stock has risen by 3.57%, but it has significantly underperformed over the longer term, with a year-to-date return of -22.60% and a staggering -53.64% over the past year. Despite a low Debt to EBITDA ratio of 1.39 times and an attractive valuation with a Price to Book Value of 0.7, the stock's recent performance is hindered by a decrease in promoter confidence, as they have reduced their stake by 1.14% in the last quarter, indicating potential concerns about the company's future.
In the broader market context, the Sensex has increased by 1.56% over the past week, while GP Petroleums has lagged behind with its 3.57% gain. This underperformance is further highlighted by the stock's negative returns over the last three years, where it has dropped by 28.81%, contrasting sharply with the Sensex's 40.54% increase. The company's flat results in June and poor long-term growth, with net sales growing at only 6.47% annually over the last five years, contribute to a lack of investor confidence, which is reflected in the stock's current downward movement.