Adapting Olympus Pen-F lenses

[redivivus]

I am trying to adapt my Pen-F lenses to an X-T4.  (I have a Pen-FT body + 38mm/1.8, 100mm/3.5, and 150mm/4).    I bought a Fotodiox adapter on Amazon  (item B008BBI92Q) for $20.  The adapter is sold by Amazon so I believe it is authentic although  the logo looks  different than the one depicted.   Unfortunately it does not work well -- the lenses do not consistently lock into the adapter  -- sometimes they do on the first try, sometimes I need to futz a lot until they lock.    Any suggestion?  Do I have a bad copy?   I see a Fotasy adapter on Ebay for $12 but it looks identical.  Or shall I bite the bullet and buy a  Kipon adapter? ($77 from B&H -- ouch!  But besides Fotodiox/Fotasy  and  Kipon I didn't see any other makers.)

Many thanks for any help & Happy New Year! -- Red