Selling to county council

I believe my tenant will dig in her heels and stay put and overhold also there is nothing to rent locally for close to what she is paying, unless the council can house her I will have a massive fight on my hands.
 
I sold or thought I sold my 3 bed house with hap tenants in situ to SDCC the process started in August 2023 ,had the surveyor out the valuation done and agreed a price, I send contracts out to them and waited and waited several months later today I get a letter from them saying that they were not going to purchase the property due to due diligence checks.

This has been a total waste of time, and would not recommend dealing with SDCC.