Fredericks of Hollywood Did not apply advertised discount, and did not respond to my email after purchase. Delayed return process, and has refused to process my refund even though i returned products on time.

1. I ordered some items via an instagram feed where i was promised a 25% discount, when i checked out, the discount was not applied and I ended up paying higher. I emailed them with a complaint but it was too late and the order processed. 

2. I received the order and it was not as expected. I emailed for return process and it took 2 emails and about 1 week or more to get a response. 

3. I mailed package out prior to and in good time before the 30 day return expired and received an email today that the return was processed 4 days after the 30 days expired. 

It made no mention of when the return was received, which I am super sure was before the 30 day return window. The company has used delay tactics in the return process to ensure I dont get a monetary refund.