As @IndyMike told you, the PLM address is not correctly written to your devices, or if everything worked correctly after the PLM swap, then the existing PLM is probable on the way out.
How many Insteon devices do you have?
Go to Tools - Diagnostics - PLM Info/Status. Does it show the PLM connected?
Try checking the PLM Links Table under Tools - Diagnostics. If the number doesn't equate to the number of devices you have, then you have confirmation of what we are telling you.