Freehold issues and leaseholds not paying service charge?

I wonder if someone could give me some advice, I’m a leaseholder of a flat that I purchased some 17 years ago in a block of 155.

The service charge was around £2,500 per year, now gone up by another £1,200 for a reserve fund as there is no funds.

The Freeholder managed the property, but just took the money and did very little work.
This was once a lovely prestigious block with a concierge, sauna, gym and swimming pool, but over the years, due to lack of maintenance, these are no longer in use, over 7 years now, the property had lost valve compared to comparable next the road by up to 35%, the deteriorated got so bad that enough was enough, we managed to require RTM (Right to Manage) after a four-year battle, but the problem I have, quite a few of the tenants didn’t pay the service charge, I believe around 15, but due to GDPR not 100% sure as RTM board wouldn’t give these details.

I can understand the reason why people withheld the money, the problem now is that a few people have got used to not paying which put the pressure on others and the only way to get this resolved this to issue legal notices, but RTM does not have the authority abound this point, if the non-payers ignore the notice, the Freeholder are the only ones that can instruct a 146 section and they’re not interested. my question is

What can be done to ensure the Freeholders are held responsibility for the negligence and inability to keep the building in fit and safe condition.

How can the other leaseholder be forced to pay the service charge, I think it’s completely unfair that we are paying whilst others are getting away with it, or should I just stop also.

Thank you in advance.

Scott