Buyer paid to my Sibling who has no SPA

Good afternoon. We (me and my 5 siblings) sold our lot. The buyer initially paid a down-payment to each of us while the transfer is being processed by my elder brother. My brother has no SPA to represent us to the buyer that is why the buyer pay to us individually. My other siblings were able to ask for additional payment from the buyer leaving maybe around 100k each as uncollected payment for their share. Me on the other hand was paid almost 50% of my share only. Everytime I ask my brother when the payment can be collected, he always tell me that the documents are still in process. Lately, when I asked the buyer, I was told that he already paid my brother in FULL and that the title is already with them. I told them that since my brother has no SPA, payment for each of us should have been remitted to us individually and not to my brother who now doesn't want to give me my money.

Can I still go after the buyer and ask for the payment since technically, I was not paid in full by them? She, the buyer, should in turn force my brother to pay them back?

Please help me what to do?

Thanks in advance

Yes you can annul the sale. The property being sold here is a property in co-ownership. The rule in co-ownership is that if there is a sale, all must agree or all of the parties must have consented. If this will not happen, you just pay back what you have received and annul the sale.

thanks a lot for your reply. At least I know that I have legal basis to go after them.

cheers