Product: Money transfer, virtual currency, or money service

On XX/XX/2019, I logged into my Wells Fargo ( WF ) online account and sent {$100.00} to my sister via their XXXX money transfer function. Per the instructions on WF 's site, my sister should have received a text notifying her of the incoming money transfer and provide her with instructions on how to register her mobile number and bank account in order to receive the funds. My sister never received a text or email notification. I waited 3-4 days to see if perhaps it was delayed, but she never received anything. I asked her to download the XXXX app and set up an account to see if once her mobile # was registered in their system, the funds would come through. My sister set up a profile with XXXX, after waiting 1-2 more days the funds still never came through. 
On XX/XX/2019, I contacted Wells Fargo to inquire about the transfer. I spoke with XXXX who indicated that between the dates of XX/XX/XXXX - XX/XX/2019, there was a technical issue at XXXX that prevented some money transfers from processing correctly. She then opened a dispute/claim ( # XXXX ) to research the matter and said they should be able to locate the funds and return them to my account. 
On XX/XX/2019, I received the attached letter from Wells Fargo indicating that after researching the matter, they are showing that the funds had been accepted/processed, so they are unable to stop or reverse the funds back to my account. I checked with my sister who confirmed that she had not received the funds. I then called Wells Fargo and spoke with XXXX in their Claims Dept. XXXX reviewed the claim notes and notified me that their research found that the funds were processed and received by a XXXX user, but that the name did not match my sister 's name, the intended recipient. She then stated that perhaps my sister 's mobile # is attached to another customer 's " token '' and that may be what caused the funds to go to the wrong person, but because the transfer has already been processed, they could not help me any further and that i would need to work with XXXX to research further. My sister has had the same phone # for almost 10 years and she established a XXXX account using that phone #, so i'm not sure how it could be connected to another person/token. 
After speaking with XXXX I contacted XXXX and spoke with XXXX regarding the matter. I conferenced my sister in on the call so that she could verify her XXXX profile information to allow them to confirm if any funds had been received. XXXX confirmed that since setting up her profile on or around XX/XX/2019, no funds have been received. Although he could see that the funds had not been received by my sister, XXXX stated that he had no way to trace the transaction from Wells Fargo to see where the funds went. He then instructed me to work with Wells Fargo to resolve. I called Wells Fargo back and spoke with XXXX (? ) in the Claims dept., and was told the same thing XXXX had told me. He said they have no control over the XXXX application and even though i used Wells Fargo 's website to send the funds, once it's processed they have no means to research further or retrieve the funds and to work with XXXX. Long story short, both Wells Fargo and XXXX keep sending me back and forth between the two institutions stating that neither have the ability to see where the funds went and that neither can refund my money to me. 
All i want is my {$100.00} back. PLEASE HELP!! This has been a terrible customer service experience with both companies. If they are in a partnership together, one would think they would have an established process to resolve incidents like this and the ability to trace the movement of funds from one entity to the other via some type of trace / transit / reference # or something.