It may have been:
Florida National Guard, assigned to the 53rd Infantry Brigade Combat Team, deployed to Ukraine to train with local forces.
160 members of which deployed in November last year.
training and advising and mentoring Ukrainian armed forces. The troops, assigned to the 53rd Infantry Brigade Combat Team, are part of the Joint Multinational Training Group-Ukraine.

53rd Infantry Brigade Combat Team in Ukraine.
“currently serving there in an advisory or ‘train-the-trainer’ role with the Ukrainian Armed Forces at the Combat Training Center-Yavoriv,”
Col. Anton T. Semelroth, a Pentagon spokesman.. said that U.S. special operations forces regularly conduct exercises with their Ukrainian counterparts.
He declined to say how many American troops are currently deployed to Ukraine, citing security concerns.
What U.S. troops are already in Ukraine? (Dec 2021)
That’d be the Florida National Guard 53rd Infantry Brigade Combat Team, which recently took over for the Washington National Guard’s 81st Stryker Brigade Combat Team.
“The U.S. recently delivered two decommissioned Coast Guard patrol boats to Ukraine’s navy.
And Ukraine’s defense intelligence chief has said its ground forces have been firing U.S.-provided Javelin anti-tank missiles at Russian or Russian-backed forces.”
That also fits in with the drones info:
Company B, “Zombie Hunters,” 53rd Brigade Special Troops Battalion, Detatchment-1 serves as the only unmanned aerial systems platoon in the Florida Army National Guard.
the unit is comprised of two teams, the launch recovery section and the operations section. The unmanned aerial vehicles are the Shadows, which combined with the launching system, its operators and maintainers, make up the complete unmanned aerial system.
The Shadow’s types of missions include military reconnaissance, forward observation and using them as a first responder.
Soldiers from Company B, Special Troops Battalion, 53rd Infantry Brigade Combat Team are spending weeks in the field .. flying, testing and maintaining a fleet of four aircraft which will provide commanders with valuable reconnaissance, surveillance and target acquisition capabilities.
“The Shadow Unmanned Aerial System will be a valuable asset for the Florida National Guard,” said Col. Perry Hagaman, the state aviation officer. “The ability for ground commanders to operate within their own three-dimensional battlespace will greatly assist units such as the 53rd Infantry Brigade Combat Team in conducting their federal mission.”

https://www.wfla.com/news/pinellas-county/53rd-infantry-brigade-combat-team-set-to-deploy-to-ukraine/
https://www.cnbc.com/2022/02/12/pentagon-orders-departure-of-us-troops-in-ukraine.html
https://www.defenseone.com/threats/2021/12/the-d-brief-december-09-2021/187416/
https://www.nationalguard.mil/News/Article-View/Article/577389/florida-guard-fields-shadow-unmanned-aerial-system/
https://www.army.mil/article/254003/more_u_s_troops_deploying_to_europe_guard_leaving_ukraine
https://reservenationalguard.com/reserve-guard-news/florida-guardsmen-shuffled-out-of-ukraine-amid-engagement-preparations/
https://taskandpurpose.com/news/florida-national-guard-ukraine-russian-invasion/