1) you never said the service could fail, you told him to pay for an IMEI unlock.

2) he told you he did not know the reason, why would he pay you for an IMEI unlock only to find out it won't be unlocked and also he has to pay 800$ to unlock it legitimately?

3) your thread never mentions you can fail or that the unlock is not possible if payment is owed to company. 

4) your thread never mentions any sort of restrictions regarding reasons for the lock. 

 

You cannot claim you did your service because he did not pay you to find out the reason of the lock but to unlock it, whatever the reason is. I also doubt that your unlocking company is legitimate. I find it funny that you wanted him to pay 20$ for an esim (????) and then wanted him to pay 350$ on top of what he already paid to unlock it. With this logic, you can say the same to all customers. Amount is owed, pay 50% to me and get unlocked.

 

You charge for a service. This service is what customers paid for. If service is not completed, then you have to refund the customer. 

I think I was clear enough,
1- The unlock service does not fail
2- Unblock the service, since it came back and was blocked for not paying in t-mobile it is not my fault, he owes a bill of $750 and I told him he can pay half
3- It doesn't fail, but I think the person knows if they owe the company
4- I said clearly that I was unblocking the internet network for use throughout the world

The people who contracted the unlock imei turned out well if they did not owe money to the company, even the information of the $700 that they owe is public, you can even enter the t-mobile page and see the invoice that they owe, I do not need to steal from them to another person telling them to pay 50%.

I was clear enough in the thread and for that I made an F&Q, I told him that I could give him another service that I provide, but money is complicated when I fulfilled my part, it is his fault if he owes money.

It's logical, I'm not going to reimburse you I told you that I would give you another free unlock, the phone is unlocked from imei, the problem is already directly with the company where you took it where you owe the $700

If you already want to have it available, pay the money you owe to t-mobile, it is not necessary for you to send it to me, I simply offer a service that was fulfilled that was to unlock, if you want to use it you must pay the rest to the company

I think I was clear in the post of sale, the service is to unlock imei and use any internet company, I told you that the only solution was to pay the outstanding to the company or that if you wanted I gave you the service on another cell phone, because I can't do anything else, if you knew that you owed $725 to the company so that you contacted?