if tactics was working and now they're not then maybe complacency has set in, what is your morale like? try having a team meeting and if you are stuck in team talks listen to whoever has the highest man management rating out of your staff
out of curiosity what is your tactic? how long did it work for and who have you lost against how long is this bad patch?
Epic has it completely right give a team talk maybe a tactic tweak if you still need help add me via steam at thegamingnerd1019
or skype at wyattcameron1
HF AND GL