Without your code, but just from the error message, it seams that there is some issue with your connection string.
You can use the code below for test:
import pyodbc
from sqlalchemy import create_engine
import urllib
params = urllib.quote_plus \
(r'Driver={ODBC Driver 13 for SQL Server};Server=tcp:yourDBServerName.database.windows.net,1433;Database=dbname;Uid=username@dbserverName;Pwd=xxx;Encrypt=yes;TrustServerCertificate=no;Connection Timeout=30;')
conn_str = 'mssql+pyodbc:///?odbc_connect={}'.format(params)
engine_azure = create_engine(conn_str,echo=True)
print('connection is ok')
Hope it helps. And please let me know if any further issue.