Did Sri Hanuman receive any curse due to which he forgot his powers?

The authentic text on Ramayana is Valmiki's Ramayana. It does not contain any such incident.

We can notice that in the entire Kishkinda Kanda and in Yuddha Kanda, Sri Hanuman acts at the orders of Sri Rama, Sugreeva, Jambavanta, and will not show his strength unnecessarily, give unsolicited advice, acts on his own. He remained in the side lines, working either under Sugreeva or Angada, as the case may be till then. 

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Sri Hanuman did not receive any curse, due to which he forgot about his strength. 

It is a Myth created in Uttara Kanda.

The following version of story is available in Uttara Kanda of Ramayana, which is an interpolated story.

“O Rama, receiving these favours which filled him with power, and with the temerity natural to him, Hanuman resembled the ocean that is overflowing.

“In his intemperate ardour, that bull among monkeys shamelessly began to create trouble in the hermitages of the great Rishis. Scattering the spoons, jars, sacrificial fires, and heaps of bark used by those peace-loving Sages, overturning and shattering them, by such exploits, he, who had been rendered invulnerable to all brahmanic weapons by Shambhu, distinguished himself.

“Knowing from whence his power was derived, the great Rishis bore with him, nevertheless, despite the warnings of his sire, Kesharin, the son of Anjana exceeded all bounds, whereupon highly indignant, those mighty Rishis, born in the line of Bhrigu and Angiras, cursed him, O Prince of the Raghus, without, however, giving rein to their full anger and irritation.

“They said:—

‘Since, in the knowledge of your power, 0 Plavamgama, you dost harass us, by the adverse effect of our curse you shalt become unaware of it for a long time, but, when it is remembered by you, you shalt be able to wield it effectively.’

“Thereafter, the knowledge of his powers was taken from him in virtue of the great Rishis’ words and, from that moment, Hanuman ranged the solitudes in a placid mood.

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Angada and other vanaras loyal to Vali might not be aware of Sri Hanuman's prowess, as the latter was a close associate of Sugriva and was away from Kishkinda, alongwith Surgriva, for longer duration. However, Jambavata knew the prowess of Sri Hanuman, being senior member of Kishkinda kingdom.

Vanaras got exhausted and felt helpless and Angada and other vanaras even went to the extent of resorting to fast unto death.

बंधनात् च अवसादात् मे श्रेयः प्रायोपवेशनम् | अनुजानंतु माम् सर्वे गृहम् गच्छंतु वानराः || ४-५५-११

"Fast unto death behoves me than trammels and tramples, thus you all be acquiescent to my proposal and you may go back to your dwellings."

सुग्रीवम् चैव निन्दन्तः प्रशंसन्तः च वालिनम् || ४-५५-१८ परिवार्य अंगदम् सर्वे व्यवस्यन् प्रायम् आसितुम् |

While disesteeming Sugreeva but esteeming Vali, all of the vanara-s have gathered around Angada deciding to sit down for fasting unto death in step with Angada.

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After Sampati's narration about Sita, the major vanaras explain their respective capacities in jumping over the ocean spreading over 100 Yojanas. Everyone, including Jambavantha were found to be unfit for the task. Though Angada can do that task, he was not allowed to do so being the crown prince.

As everybody got dejected, Jambavanta praises Sri Hanuman and gently advises to achieve the task. As Sri Hanuman respects elders and duty bounded, he started showing his real strength.

That is all.