This is absolutely the right place to ask! Thank you for reaching out!
You can go to https://support.mnt.re/ to get step-by-step instructions of how to figure out what is wrong with your Pocket. You first answer “Pocket Reform doesn’t turn on” and then the answer to the second question might be “The OLED stays blank.” The first advice then is to toggle the standby switch. Does toggling the switch to off and then back on help?
If not, bridging pins 2&3 of J1 as the guide suggests lets you check what is wrong with your Pocket without the charging board in the loop. I also wrote about this here: Running the Pocket without batteries (bypassing a broken charging board)
Let us know how it goes!
P.S.: If you want to sell your unit, this forum is also one of the places to do so. 