Selling and buying back stock holdings on the same day

I know short selling is haram because selling whats is not in my posession yet is not permissible, but I am not able to find if these boundary level conditions fall in permissible or not permissible side. My question here has two parts: 1. If I **sell my holdings** (old stocks that I already have in my DEMAT account) and **buy the same quantity of the same company again on the same day**, will it be considered as halal? Although I am making a different transaction here, it would be an equivalent of exiting that position on the same day before my sell-transaction was completed with delivery. 2. If the answer to question 1 is positive, will it be permissible if I do the same, multiple times in a single day with the same stock?