@buddy-99
I need to ask a dumb question - just to make sure... You performed work for ACL several weeks ago and this check is modest payment for those services, yes?
Scammers will often send a large check to somebody in advance of work being completed, asking them to deposit the check and use the funds to perform a "shop" (such as purchasing and mailing gift cards). I had no issues with my recent ACL check, so the fact that yours got flagged makes me wonder if this is possible - in which case you should NOT follow through with the shop. These scams are very common and ACL's name is used in some of them.
Otherwise, it just sounds like your bank is doing its due-diligence to protect both you and itself.
Hard work builds character and homework is good for your soul.