Many digital scales will "correct" to the last close weight. Manufacturers do this because no scale is perfect, and it can make a scale seem more accurate.
Maybe you did lose half a pound, but it tells you the same weight as last time. A few years ago I bought two scales, and I chose these particular scales because the brands claimed they did NOT do this. But I've found that they both do, particularly if you weigh yourself frequently.
Of course we all know that weight loss isn't a smooth journey. Sometimes the scale really doesn't move, and that's ok. Just stick with the program, and you will get where you are going.
But if you think your scale may have settled on a previous number, here's a little trick. Pick up something heavy, and reweigh yourself. This should force the scale to move away from the old number. Now put down the heavy thing, and reweigh yourself again. This should give you a new number.
I usually weigh myself once a week. Weighing more often is not very meaningful because weight will fluctuate from day to day, mostly from the amount of water in your body. If you've had salty food recently, this will tend to increase your weight.
Knowing this, I've found that I don't usually gain weight from fat while on vacation. I will be 2 pounds higher, if I weigh as soon as I get back. But if I wait a couple days, so the extra salt from restaurant food is out of my system, I will be the same weight as when I left. (Of course I don't know how you vacation, so your results may vary, lol.)
You should also be aware that scales can lose accuracy over time (and some just aren't that great to begin with). When I bought those 2 scales a few years ago, I did so because I realized my old scale was getting farther and farther off. This became obvious when it started giving me crazy results, lol. I bought 2 scales so I could check them against each other, to make sure one wasn't drifting up or down. They are usually within a pound.