The amount of daily reward jokers is written in the lower left corner, when you open your daily reward window:
As Xarkost already wrote, the amount of jokers will be consumed depending on how many days you did not pick your daily reward. Players can have a maximum amount of 3 jokers, that means, you can skip picking your daily reward for 3 days and take it on the fourth day and then all jokers will be consumed. In this case your streak will be continued. If you did not take your daily reward for longer, the streak will be reset, as written on the official page:
Each character receives one daily reward joker on the first server save of each month. They can accrue up to three of these daily reward jokers, which will be displayed in the reward wall. The character selection receives a new column which shows whether the daily reward has been already collected since the last server save.
The new daily reward jokers each compensate for one server save cycle during which the daily reward has not been collected. For instance, if you have two daily reward jokers and forget to collect the daily reward for two server save cycles while having an active streak of five days and only collect the reward within the third server save cycle, the two daily reward jokers will be used up and your streak will be increased to six days. If you would not have at least two jokers in this case, the daily reward streak would be reset when collecting the reward.
Source: https://www.tibia.com/news/?subtopic=newsarchive&id=5808