Delayed Offer Letter

I originally interviewed for an EB last November for their NYC SA program and they kept me on hold/waitlist for one month before sending the official rejection letter in mid-December. One of their division head reached out to me back in Early January this year again stating that they are expanding their program to the mid-west and would love to offer me an internship position for their new program. I had a call with the individual and they mentioned the offer is "99% mine" and asked me to get on a call with another individual who is overseeing the new SA program. I had the call and they mentioned that HR would be in touch within two weeks (Mid-February) with the formal offer letter.

I didn't hear anything by mid-February so I reached out again and they mentioned they have faced some unexpected administrative challenges and wanted to get on a call to discuss further thoughts and updates. I replied asking to schedule a time for the call but haven't heard back in almost three weeks. I am kinda getting worried now about this issue and I was wondering if anyone here has faced similar issues before or might have a take on this situation.