Connection manager :changes are not saved after edit ,the package still retains the old server name

I copied a prod pkg to my local machine and opened it in BIDS .The package had a oledb connection to sql server .I wanted to chnage it and point it to my local machine sql server.But whenever I make changes in the connection manager the settings are not saved .

bids 2008r2

What might be the issue?

Mudassar