My bank caused my refinancing interest rate expired..

[yrre7]

Hi guys,
I figure this might be a place to get helps.
Anyway, long story short. I have locked in my interest rate from a bank, the loan doc were ready and sent to the escrow on the last day of the interest rate expiration date. My loan officer told me to call the escrow to set up an appointment. The escrow seems realized the expiration date being only one day away, and the escrow called the bank funder (not loan officer) to confirm they would have to let us sign the doc 2 days after the expiration date. The bank funder says it's ok to sign 2 days after (on Friday). We tried to contact the funder again on Friday to ask her again if it's really ok to sign. She didn't pick up. We didn't know what to do and just went to the escrow and signed everything. On the following Monday, escrow called the funder to confirm the signing date being later than the interest rate expiration date. The funder says OK again. We listened to the funder. Everything seems good and got the money transferred to escrow on Monday.

Now today this morning, got a call from the escrow saying the the funding got stopped due the expiration date. What can I do? Isn't it apprarently the bank's fault? Now I missed my good interest rate 4.875% and facing the rising rate. I am not sure if we can get the rate we wanted again. My loan officer told me I had to re-lock in the new rate within 30 days, otherwise I have to redo my loans application, and I don't want to do that because it might cause me not able to refinance.

Is there any legal advice I can take here?
Thank a lot.