Here are some methods that were available at that time:
Achievements: Completing certain achievements in PUBG Mobile could reward you with rename cards. Check the achievements tab and try to complete various tasks to earn rewards.
Progressive Events: PUBG Mobile often holds events that reward players with rename cards as they complete specific milestones during the event.
Shop Offers: Occasionally, renamed cards may be offered in the in-game shop for BP (Battle Points), which you earn by playing matches. Keep an eye on the shop for such offers.
Redeem Codes: PUBG Mobile sometimes releases redeem codes as part of promotions or events. These codes can be used to claim various rewards, including renaming cards. Follow PUBG Mobile’s official social media channels and websites for information on redeem codes.
Royal Pass: If you purchase the Elite Royal Pass or the Elite Royal Pass Plus (formerly known as the Royale Pass), you can earn renamed cards as rewards when you reach certain tiers or levels.
Daily Sign-In: Sometimes, PUBG Mobile offers rename cards as part of the daily sign-in rewards. Make sure to log in daily to see if this is available.
Participate in Tournaments: Some tournaments and events may offer renamed cards as prizes for participating or winning.
Friendship Bonuses: PUBG Mobile may have features where you can receive rewards, including rename cards, for playing with friends or adding new friends to your list.
Team Up and collaborate: Occasionally, PUBG Mobile collaborates with other brands, movies, or games. Check for collaborations and events related to these partnerships, as they may offer renamed cards as rewards.
Community Giveaways: Some PUBG Mobile communities and fan groups may host giveaways or events where you can win rename cards. Participate in these community activities for a chance to obtain them.