Dignity refuse to pay me by giving me delay tactics

I have a small scheme with Dignity they are my underwriters , I've payed everything in order and I've been in business with them even though they always giv me hard time before they cum throu with payment .. last thing they do that got to they real dont wanna pay clients money . They busy referring me from lady Called Sibongile and even to her she'd say shes waiting for feedback now its almost three weeks no payment they looking for all kinda escape plan not to pay .. they are ******** they will refer to payment of march but we are on July whereas I've paid all the money i have even extra premiums with them everythn they make it like a delay tactic not to pay