If you have lower body mobility issues that lead to swaying and sliding in putting, your clubface will not be square during impact. This is a very easy exercise you can do at home while you stuck during corona virus lock-down or after. Just use a door inside or outside your house and use your phone to film yourself during this practice. You cannot move the door, if you do, you failed. Try to practice your putting stroke like this as much as you need, until you don't move the door anymore.