Here is the solution to your issue [quote]:
Monthly TP Spending Limits Applied
Jul 3rd, 2017
In order to prevent payment fraud-related issues from affecting the game, starting from this week’s scheduled maintenance (July 4, 2017), we will be adopting a monthly TP spending limit for Steam accounts that have a shorter payment record since their time of creation.
This means that players who have made fewer purchases on Steam since creating their account (in accordance with the account purchase information provided by Steam) may be restricted from using more than 300 TP in-game per month. After attempting to use more than 300 TP in one month, players with TP limits will see a message alerting them of this monthly restriction.
If you find that a TP spending limit has been applied to your account and want this restriction to be removed, kindly send a ticket via our Support page under the “Payment” >> “Reset TP Spending Limit” category so we can verify and process your request individually.
Please note that this TP limit applies only to how much TP an account is allowed spend in-game. It does not restrict the amount of TP that players are able to purchase on Steam.
It doesn’t matter how old the account is but how often you bought TP via Steam.
You only have to send a ticket on the main site via the right support ticket channel (as explained above) and your problem will be solved (it literally took me 10 seconds to find that answer via the search function on the main site).
you cannot see it in game as far as I know, so you have to calculate the amount manually by subtracting every purchase from 1000 TP.