Non payment and used our vehicles

Good day. We are a small transport company and have been operating for 2 years now. I need your help plesse in regards to a company that doesn't want to pay our company what's due to us. The agreement was that tgey will pay after 30 days . They used our vehicle for 2 months and only paid us for one month and after we fought with them. It's now 2 months and they haven't paid us the remaining amount . They have been smooth talking us, ignoring our calls and also message. At 1st they said they work on a 30 day period and come pay date they said they made a mistake it's a 60 day period. The debit order for the car bounced n accumulated interest. So eventually they paid after 60 days the 1st amount. The second payment is still not paid and it's over 60 months now.

Tsheola Dinare Tours and Transport must pay up. They used

Kind Regards