I have Arduino Uno
IR receiver works
OLED I2C 0.96' works
but they in one code says : "SSD1306 allocation failed"
Maybe a problem with the code that you did not post.
Please read the forum guidelines to see how to properly post code and some information on making a good post.
Use the IDE autoformat tool (ctrl-t or Tools, Auto format) before posting code in a code block.
Post links to libraries not included with the IDE.
Maybe a problem with the wiring that we cannot see.
Please post a schematic or wiring diagram. Written descriptions are always more ambiguous than a drawing. Hand drawn, photographed and posted is fine. Include all pin names/numbers, components, their part numbers and/or values and power supplies.
Photos of the wiring are often useful.
Check all connections.
I have similar parts on the workbench but they do not work either, possibly because they are not connected or powered.