One of the causes of blocked ear is definitely impacted wax in the ear canal.
Wax dissolving drops need to be put 3-4 times a day for 1 week and then an ENT specialist needs to clear the wax with a suction apparatus.
Next Steps
However there maybe other causes of blocked ear. So, before using self medication, please take the opinion of an ENT specialist
Health Tips
Trying to clean the wax with an ear bud is risky as it may injure the ear drum