Bubble recently made some adjustments their overall pricing structure which affected the Personal plan as well.
The current/new pricing for personal plan is $29/month ($25 with yearly subscription) however,
if you had a bubble account before mid-August 2019 (approx), you have the option to stay with the old (legacy) pricing model for 2 years.
Old (legacy) pricing for Personal tier - $16 month
New (current) pricing for Personal tier - $29/month ($25 yearly sub)