ZRS Management review: Account sent to collections

Hello I provided a 60 day notice to the leasing office in December 2020 and moved out the second week of March 2021. At the time of moving I provided a forwarding address to the leasing consultants and was told that all I had to pay was $3000, which is the option 1, in my lease which stated that I could pay two times the base rent and that would suffice my lease oligations. Now June 2021 I received a collections call from IQ Data who stated that I owed ZRS Management over $5000 for my lease and pay due water, sewer and trash bills. I explained to the collector that I had provided my new address to the leasing office and had not received anything in the mail. I then called the office and spoke to Anna Lieghn the assistant property manager and she stated that due to COVID-19, lots of accounts were sent over to the collections company by mistake and that ZRS was working on getting the issue fixed and that someone would reach out to my by the end of the week to set up a payment plan and remove the account from collections, since it was a mistake on the company end. I call the complex the next week and everyday that I called the managers where not available at all and now its on my credit and I have IQ Data specialists who are very rude and aggressive. This is not fair and it's unethical. I have never missed paying my rent while a resident there and should have been treated with more respect than how I was treated.