Decrypt the SQL Encrypted AES-128 column value in c#

Question

I Have table with the Symmentric (AES-128) Encryption  on table. 

How can  decrypt and use it in c# level. I am able to dycrypt again back Sql level but i want to decrypt in c# class of that. 

 

Geettign Error : 

For  byte[] cipherBytes = Convert.FromBase64String(cipherText); 

"The input is not a valid Base-64 string as it contains a non-base 64 character, more than two padding characters, or an illegal character among the padding characters"