^^
No matter how experienced in trading you are, it's almost impossible to predict what the price would be or whether it will go up or down in the next 15 or 30 seconds. First because the difference between the starting price and the ending price is almost negligible and second because 15 or even 30 seconds isn't enough to analyze the market.
As you said, it's a luck based game so just enjoy it.
I don't really think it mainly base on luck there's still need of some analysis in order to get a higher chance of winning though luck may have a role here but it's not the basic.
Though entirely it kind be seen as a fun prediction of bitcoin price.
There's always a trend and if you have a photographic memory you can catch that trend to make good results in your betting since the time frame is within 30 seconds you can catch the trend on 3 to 6 successive betting or even more before there is a shift, you will need big funds and total engagement to have a favorable results its fun and challenging.
Also Op please, is there any chance of adding other third-party aside Changely, which may accept lesser minimum deposit with other crypto.
The other alternative with good reviews is Gate.io based on this articles
https://www.g2.com/products/changelly/competitors/alternativesSo what would you recommend loading is good but revising the script will add more loads to the script its better to use your in-wallet swap I always do it on Trust Wallet then I transfer my Polygon on Bitwinup.