I got mine November of 2018 i believe. Never had any problem with OTA updates until the update in February to 2.0. That one came with the January 1 security patch. Every update since then has been forced. One by UBREAKIFIX, and my last one was through Odin just a day or two ago. The phone was purchased though an AT&T store not too far away and replaced my Note 5.
When I first got it, it was running Oreo. Then the update to one ui 1.0 with all the security updates coming once a month. Then in February 2020 I got the update to 2.0. Since that update, nothing unless I had the update forced in.
Nothing shady in the purchase of the phone, nothing unusual. The only physical problem I've had with the phone was a cracked screen, last month.