WFSE TA- thinking about not paying union dues

With this TA I am disappointed in the COLA and struggling to cover costs of living. I’m thinking about telling payroll to stop withdrawing money for me to pay union dues. If I do this, I understand that I would still benefit from any CBA and be covered by the terms and conditions.

What are the downsides of not paying dues? My union rep is not very helpful, I’ve talked to them once. I have a good relationship with my manager and HR.

What would I actually lose if I stopped paying union dues?