Firstly I would like to know whether you are taking any medication related to other systemic problem likely some medications have side effect of oral ulceration
Secondly check your salivary flow, are you suffering from dry mouth or not.
Thirdly apply T-bact ointment with hexagel and stolen gum paint it will greatly reduce your oral ulceration.
Next Steps
visit oral pathologist or well qualified post graduate MDS doctor like me for proper treatment plan