DeNA has posted an announcement regarding the adjustments to Mission Bingo and their reasoning behind the changes.

Mission Bingo Adjustments

We have received many inquiries regarding the adjustments to Mission Bingo: Beginner, Mission Bingo: Intermediate, and Mission Bingo: Advanced that were introduced with the update to Ver. 1.12.0. We regret any inconvenience caused by not providing enough information about these adjustments. In this notice, we will explain the details of these adjustments, our reasoning behind them, and our future plans.

Adjustment Details

• We adjusted the content and rewards of the missions specified on bingo card squares.
• Even if you have completed bingo missions before this update, you can still attempt them again and collect the rewards from each square.
• If you collected any bingo rewards or bingo blackout rewards before this update, you will not be able to collect them again.

Reasoning Behind the Adjustments

With the Ver. 1.12.0 update, we aimed at providing an even more enjoyable experience to those new to Pokémon Masters by making changes such as removing courses and Daily Vouchers. Along those lines, we readjusted the content and rewards of missions.

At that time, in the interest of fairness, we decided with careful consideration not to allow players who had already collected bingo rewards and bingo blackout rewards before the update to collect them again. We appreciate your understanding of the details of these adjustments and our reasoning behind them. To the players who have sent us inquiries regarding this matter, please accept this notice as our response.

Future Plans

We will make adjustments to menus such as the Mission Bingo screen so that it is clear whether or not you have collected completion rewards. Note: Details such as the timing of these adjustments will be explained in a separate notice. Once again, we sincerely regret any inconvenience caused.

Source: https://pokemonmasters-game.com/en-US/announcements/Trouble_2070h_1W_2