Should we hold on to altcoins which we have invested and see the price dropping every moment or it will be better to sell them and buy it again when the value pumps ? I have already lost a good margin of profit with the ripple I don't want to make the same mistake with the Lumens which I Hold so should I hold on or sell out ?
Depends on your coin to be honest. You should just invest in it properly. If the coins are Paragon, Stellar and Cardano them you can always hold them for some time and then sell when it rises.
I do not understand those "traders" who are wondering - "and not to sell me all my coins when they lost value." Perhaps these people do not receive a salary at work, while they themselves pay their employers))
can be seen on the graph the price of coins that have elevated high enough. able to produce a much larger profit from selling coins at this time. by selling it to be able to generate more profits in the future. so I strongly recommend to sell for now.