In order to check this challenge you need to remove the validation rule of account that you might have created for other challenges.If this does not work, I would suggest you create new trailhead playground and work for challenge.
Please mark it as solved if my reply was helpful, it will make it available for others as a proper solution.
There is a validation rule on account causing the problem..make sure the account number has only numeric value.
--
Thanks,
Prashant
In order to check this challenge you need to remove the validation rule of account that you might have created for other challenges.If this does not work, I would suggest you create new trailhead playground and work for challenge.
Please mark it as solved if my reply was helpful, it will make it available
for others as a proper solution.
Best Regards,
Sandhya