Pursue a small claims court

Hello everyone,
I want to know- and insight on this matter would be appreciated. I issued a section21 last June 2024, but the tenant refused to move out as she claimed section 21 is invalid- she would not tell me why- I have sought advice from a solicitor with a fixed fee I’ve been emailing the solicitor back, and forth - and would give me further advice,
As the tenant has been short-paying her rent for several months and the arrears are now £2310.00.
Attempted to call the Citizens Advice Bureau for legal advice- I was held for 35 minutes on the phone and in the end, an automated phone message said no one can answer your call.
My question is, Can I pursue a small claims court case against the tenant for the overdue rent while the firm is pursuing an S21?.

You need to sort the eviction out first. I believe if evicted under Section 8, an order for the arrears can be made at the same time. However, you seem to be using S21.

Are you confident your ‘solicitor’ is doing the job properly. Many LL would recommend an eviction specialist rather than a ‘jack of all trades’ solicitor. They wll check if your S21 was correct, and can start to enforce it.