There were a lot of problems that the Weimar Republic had to face from 1919.
The first problem that the Republic had to face was the consequences of signing the Treaty of Versailles because it came with a lot of problems like the massive debt of £6.6 billion, the reduction of the army and land lost. This caused hyper-inflation, the armies blame to the government for the defeat in the First World War – the ‘stab in the back’ theory and political violence. Since the Weimar was not powerful enough with the blame from the public other parties believed that was an advantage to overthrow the government and take control.
Secondly, the invasion of the Ruhr was when France tried to invade, the government allowed the workers to go on strike and still get paid so it was useless for the French to invade in the first place but this caused a loss income from the most important industrial areas and this lead to hyper-inflation.
Hyper-inflation was another problem for the Weimar Republic because the German people weren't happy that all the prices were rising up as most of them could barely afford food and this made the Republic look weak to other countries since its currency was one of the weakest.
Furthermore, the defeat in the First World War – stab in the back theory was a problem for the Weimar Republic as the army was practically against their party. It set out a bad reputation for the government and made them weaker.
Lastly, more political parties were uprising and trying to take over the government which caused them…