Internal Limits
This will be down to table limits in the software. It will probably be displaying "you have bet your maximum" or "bet adjusted to table maximum", either top left or right. It may be possible to adjust your limits under "Options" to a certain extent. The amount of adjustment possible is set by the casino operator, and may be different from player to player, and with status (VIP's generally have higher limits).
I note that you have posted this in the "complaints" area too! You might get a "slapped wrist" for this, as strictly this is not a complaint, and this subforum is the best place for this type of general question. Most posters, like myself, will look in all threads where input may be of help, and you are no more likely to get a faster respose with 2 identical posts as with one in the "right place". Don't let this scare you off though, you are welcome to the forum, and this place is very helpful when it comes to understanding the ins and outs of playing online with "proper" money.
When you request a withdrawal, you may well be asked to produce a photo ID by the casino before they release the funds. With $300+ type action, perhaps leading to some large transactions, this will be inevitable (it should only happen once though).
If you are really "new to this" as your handle and number of posts imply, do you REALLY want to bet more than $300 a shot? There is an obscure feature in these casinos, where four consecutive wins with the max wager at Blackjack can trigger a game freeze, it happens with a win of around $18,000 in 4 or 5 hands (big bets!), and the game is disabled for 24 to 48 hours. The ethics of this has been debated here, especially given that this does not happen if you LOSE said $18,000 in 4 to 5 games!
