Also file a 5329 for 2018 with the waiver request. This can be mailed as a stand alone form. 

Do a corrective distribution for the two years in 2020. The 2020 distribution can be waived. Depending on the age of the client, you might encourage them to set up an automatic distribution each year.  If they won't do that either, seriously consider a roll over to an institution that appreciates the client more.